Stranger Danger: Some Realities of Docker Containers -- Especially in the Age of AI

[bnhf]

Let me start by saying I'm a big fan of Docker, in fact, without Docker I sincerely doubt I'd have developed any of the Open Source projects I've created in the last 5 years. Having said that, I thought I'd put down a few words on what to beware of with Docker projects -- especially in the age of AI.

Trust

When it comes to choosing to install a Docker container, having at least a minimum of trust is critical. This means there are things to look out for, such as users that are new to this forum (or any other forum you frequent). But beyond that, unless the project has been created by a company with a provable track record, it's critical the project is open source. This means the source code can be inspected, and that users can build from that source if desired.

These open source projects should be available on one of the trusted platforms, with GitHub being the leader. Users with no other projects on GitHub and no history on GitHub or Docker Hub need additional scrutiny.

Privileges

If you're satisfied with the trust equation outlined above, the next consideration is whether or not this container deployment is requesting extra privileges. These privileges can include many things, but among them are network_mode: host. If you have a comfortable level of trust with the project, then this is not unreasonable -- provided there's a legitimate reason to use it.

I recently did an experiment to illustrate this point, and in about 20 mins had a block of code that could be compiled, and then used to install anything I wanted in that container "on-the-fly". The container in question was built with no tools of concern, and had no other privileges beyond network_mode: host.

This code could have been used to install just about anything new in the container, including but not limited to: LAN scans to reveal the MAC addresses of LAN devices with known vulnerabilities; port scans for brute force password attacks and on-LAN DoS attacks.

AI

Once upon a time, it was relatively easy to identify bad actors on the Internet, as these attacks tended to be crude. Often riddled with spelling and grammar mistakes. With AI in the mix, this is flipped on its head, and posts or e-mails that are very convincing -- often devoid of any spelling or grammar issues are the new "Nigerian Prince" messages.

Posts that come in rapid succession, with liberal use of formatting bullet points, font changes and other marketing flourishes need to be given an extra look.

Conclusion

Docker is an amazing way to be able to distribute software, especially for hobbyists/enthusiasts, but it's up to all of us to remain vigilant. A docker container on your LAN, with any level of extra privileges, isn't much different from letting a stranger into your house to connect their computer directly to your LAN. There are amazing projects out there to take advantage of, as long as there's a reasonable level of caution exercised.

To illustrate the point I'm making above, I fed this post into ChatGPT to show what a little AI flair/post-processing might look like. The AI version is in the next post.

[bnhf]

What to Watch Out for With Docker Projects — Especially in the Age of AI

Let me start by saying: I'm a big fan of Docker.
In fact, without Docker, I sincerely doubt I’d have developed any of the open-source projects I’ve created over the last 5 years.

That said, I wanted to take a moment to highlight a few things to beware of when working with Docker projects — especially now that AI is rapidly evolving how code and communication are created.

Trust

When choosing to install a Docker container, a baseline level of trust is essential.

Here are a few things to keep in mind:

• Check user reputation — Be cautious with containers published by users who are new to GitHub, Docker Hub, or the forum you’re browsing.
• Prefer established authors or organizations — A project backed by a company with a known track record is generally safer.
• Ensure the project is open source — This means:
  • The source code is available for inspection.
  • You can build the image yourself if desired.
• Use trusted platforms like GitHub for transparency.
• Projects with no visible code, no history, or no other contributions should be scrutinized heavily.

Privileges

Even with a trusted project, be cautious about container privileges.

Key flags to look out for:

• network_mode: host
  This gives the container direct access to your host network, which can be risky.

Tip: If a container requests elevated privileges, make sure there’s a clear and legitimate reason.

I recently did a quick experiment to illustrate this:

In under 20 minutes, I wrote a simple block of code that:

• Compiled cleanly.
• Installed arbitrary packages inside a container.
• Exploited nothing except network_mode: host.

This could have been used to:

• Scan your LAN for MAC addresses with known vulnerabilities.
• Launch port scans, brute-force attacks, or even on-LAN DoS attacks.

AI-Generated Deception

Once upon a time, malicious posts and emails were easy to spot — full of broken grammar and sketchy formatting.

That era is over.

Thanks to AI:

• Posts are now polished, persuasive, and error-free.
• Marketing-style content (bullets, headings, etc.) can be auto-generated to gain trust quickly.
• Suspicious signs now include:
  • Posts in rapid succession.
  • Overuse of formatting and “slick” presentation.
  • No real development history behind the user.

In short: AI makes social engineering look professional.

Conclusion

Docker is an incredible tool — especially for hobbyists, self-hosters, and indie developers.
But with great power comes great responsibility:

A container running on your LAN with extra privileges is not much different from letting a stranger plug their laptop into your home network.

There are amazing open-source projects out there.
Just remember:
Stay alert.
Check the source.
Scrutinize privilege levels.
Trust, but verify.

Happy (and safe) containerizing!

[chDVRuser]

All good security practices.

I would add checking what changes are in a new release version of your container at the repository you pull it from before you update (reason I don't use watchtower auto-updates). The developer should publish some kind of release notes explaining why there's a new version, and you can decide whether to update or not.

Also, stop and remove containers and images you're no longer using.

[babsonnexus]

I feel like I've read several posts exactly like this recently... just can't put my finger on it... hmmmm...