Beware of hacked ISOs if you downloaded Linux Mint on February 20th!

I’m sorry I have to come with bad news.

We were exposed to an intrusion today. It was brief and it shouldn’t impact many people, but if it impacts you, it’s very important you read the information below.

What happened?

Hackers made a modified Linux Mint ISO, with a backdoor in it, and managed to hack our website to point to it.

Does this affect you?

As far as we know, the only compromised edition was Linux Mint 17.3 Cinnamon edition.

If you downloaded another release or another edition, this does not affect you. If you downloaded via torrents or via a direct HTTP link, this doesn’t affect you either.

Finally, the situation happened today, so it should only impact people who downloaded this edition on February 20th.

How to check if your ISO is compromised?

If you still have the ISO file, check its MD5 signature with the command “md5sum yourfile.iso” (where yourfile.iso is the name of the ISO).

The valid signatures are below:

If you still have the burnt DVD or USB stick, boot a computer or a virtual machine offline (turn off your router if in doubt) with it and let it load the live session.

Once in the live session, if there is a file in /var/lib/man.cy, then this is an infected ISO.

What to do if you are affected?

Delete the ISO. If you burnt it to DVD, trash the disc. If you burnt it to USB, format the stick.

If you installed this ISO on a computer:

  • Put the computer offline.
  • Backup your personal data, if any.
  • Reinstall the OS or format the partition.
  • Change your passwords for sensitive websites (for your email in particular).

Is everything back to normal now?

Not yet. We took the server down while we’re fixing the issue.

Who did that?

The hacked ISOs are hosted on 5.104.175.212 and the backdoor connects to absentvodka.com.

Both lead to Sofia, Bulgaria, and the name of 3 people over there. We don’t know their roles in this, but if we ask for an investigation, this is where it will start.

What we don’t know is the motivation behind this attack. If more efforts are made to attack our project and if the goal is to hurt us, we’ll get in touch with authorities and security firms to confront the people behind this.

If you’ve been affected by this, please do let us know.