A reported Free Download Manager supply chain attack redirected Linux users to a malicious Debian package repository that installed information-stealing malware.

The malware used in this campaign establishes a reverse shell to a C2 server and installs a Bash stealer that collects user data and account credentials.

Kaspersky discovered the potential supply chain compromise case while investigating suspicious domains, finding that the campaign has been underway for over three years.

  • The article mentions how to check for infection:

    If you have installed the Linux version of the Free Download Manager between 2020 and 2022, you should check and see if the malicious version was installed.

    To do this, look for the following files dropped by the malware, and if found, delete them:

    /etc/cron.d/collect
    /var/tmp/crond
    /var/tmp/bs
    
    • Back in the day when most stuff was on FTP and HTTP and your connection was crap and could drop at any time, you’d use a download manager to smooth things along. It could resume downloads when connection dropped, it could keep a download going for days on end and resume as needed, and it could abusing the bandwitdh limitations of the source site by using multiple parallel connections that pulled on different file chunks. In some ways it was very similar to how we use BT today.

      It was also useful to keep a history of stuff you’d downloaded in case you needed it again, manage the associated files etc.

      • and it could abusing the bandwitdh limitations of the source site by using multiple parallel connections that pulled on different file chunks

        Also for files which had multiple different mirror sites you could download chunks from multiple mirrors concurrently which would allow you to max out your bandwidth even if individual mirrors were limiting download speeds.

        • BitTorrent works in chunks basically, or can download it nonlinearly. Downloading from a site in a basic way gets the file from start to finish, the download manager can let you stop it and pick up where you left off, as long as the server you’re getting the file from is configured to allow it.

          https://github.com/agalwood/Motrix

          (Note: I don’t use that or any other download manager and haven’t since Windows 95, it’s linked as example only)

  • Mmmh. You kinda deserve being infected if you do things like this. Every beginner tutorial specifically tells you not to download random stuff from the internet and ‘sudo’ install it. Every Wiki with helpful information has these boxes that tell you not to do it. I’m okay if you do it anyways. But don’t blame anyone else for the consequences. And don’t tell me you haven’t been warned.

    Also I wonder about the impact this had. It went unnoticed for 3 years. So I can’t imagine it having affected many people. The text says it affected few people. And it didn’t have any real impact.

    But supply chain attacks are real. Don’t get fooled. And don’t install random stuff. Install the download manager from your package repository instead.

    • I kind of disagree. Applications often require root permissions to install themselves, since regular users can’t access certain folders like /opt, etc.

      Also, do you really think that people would actually read the source and then compile all their software themselves? Do you do the same?

      Generally though I do agree, you’re probably fine installing software from your distro’s repos but even that’s not bulletproof and also it’s not like third-party repos are uncommon either.

      • Yes. I do it the correct way. I use my favourite distro’s package manager to install software. This way it’s tested, a few people had a look at the changes, and sometimes a CI script automatically determines if the installer affects other parts of the system. I go to great lengths to avoid doing it any other way. (I’ve been using some flatpaks in recent times, though. But sometimes I also install it only for a separate user account. Mainly when it’s proprietary or niche.)

        It is super rare that I install random stuff from the internet. Or ‘curl’ and then pipe the installer script into a root shell. And when I do, I put in some effort to see if it’s okay. I think i had a quick glance at most of the install .sh scripts before continuing. So yes, I kinda do my best. And I isolate that stuff and don’t put it on the same container that does my email.

        Most of the times you can avoid doing it the ‘stupid way’. And even the programming package managers like ‘npm’, ‘cargo’, … have started to take supply chain attacks seriously.

  • I had to essentially read the same thing four times before there was any new information in this post. Not sure if that’s a Jerboa thing or what, but probably could have been avoided.

    • Yeah I agree, sorry about that. I thought that the body-text field was mandatory to fill in, so I used the introductory paragraph from the article so as not to editorialize.