cultural reviewer and dabbler in stylistic premonitions

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Joined 3 years ago
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Cake day: January 17th, 2022

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  • This video is full of jarring edits which initially made me wonder if someone had cut out words or phrases to create an abbreviated version. But, then I realized there are way too many of them to have been done manually. I checked the full original video and from the few edits i manually checked it seems like it is just inconsequential pauses etc that were removed: for instance, when Linus says “the other side of that picture” in the original there is an extra “p” sound which is removed here.

    Yet another irritating and unnecessary application of neural networks, I guess.









  • xzbot from Anthony Weems enables to patch the corrupted liblzma to change the private key used to compare it to the signed ssh certificate, so adding this to your instructions might enable me to demonstrate sshing into the VM :)

    Fun :)

    Btw, instead of installing individual vulnerable debs as those kali instructions I linked to earlier suggest, you could also point debootstrap at the snapshot service so that you get a complete system with everything as it would’ve been in late March and then run that in a VM… or in a container. You can find various instructions for creating containers and VMs using debootstrap (eg, this one which tells you how to run a container with systemd-nspawn; but you could also do it with podman or docker or lxc). When the instructions tell you to run debootstrap, you just want to specify a snapshot URL like https://snapshot.debian.org/archive/debian/20240325T212344Z/ in place of the usual Debian repository url (typically https://deb.debian.org/debian/).


  • A daily ISO of Debian testing or Ubuntu 24.04 (noble) beta from prior to the first week of April would be easiest, but those aren’t archived anywhere that I know of. It didn’t make it in to any stable releases of any Debian-based distros.

    But even when you have a vulnerable system running sshd in a vulnerable configuration, you can’t fully demo the backdoor because it requires the attacker to authenticate with their private key (which has not been revealed).

    But, if you just want to run it and observe the sshd slowness that caused the backdoor to be discovered, here are instructions for installing the vulnerable liblzma deb from snapshot.debian.org.




  • Arthur Besse@lemmy.mlMtoLinux@lemmy.mlHow the xz backdoor highlights a major flaw in Nix
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    6 months ago

    As of today, NixOS (like most distros) has reverted to a version slightly prior to the release with the Debian-or-Redhat-specific sshd backdoor which was inserted into xz just two months ago. However, the saboteur had hundreds of commits prior to the insertion of that backdoor, and it is very likely that some of those contain subtle intentional vulnerabilities (aka “bugdoors”) which have not yet been discovered.

    As (retired) Debian developer Joey Hess explains here, the safest course is probably to switch to something based on the last version (5.3.1) released prior to Jia Tan getting push access.

    Unfortunately, as explained in this debian issue, that is not entirely trivial because dependents of many recent pre-backdoor potentially-sabotaged versions require symbol(s) which are not present in older versions and also because those older versions contain at least two known vulnerabilities which were fixed during the multi-year period where the saboteur was contributing.

    After reading Xz format inadequate for long-term archiving (first published eight years ago…) I’m convinced that migrating the many projects which use XZ today (including DPKG, RPM, and Linux itself) to an entirely different compression format is probably the best long-term plan. (Though we’ll always still need tools to read XZ archives for historical purposes…)