Malicious code planted in xz Utils has been circulating for more than a month.

The malicious changes were submitted by JiaT75, one of the two main xz Utils developers with years of contributions to the project.

“Given the activity over several weeks, the committer is either directly involved or there was some quite severe compromise of their system,” an official with distributor OpenWall wrote in an advisory. “Unfortunately the latter looks like the less likely explanation, given they communicated on various lists about the ‘fixes’” provided in recent updates. Those updates and fixes can be found here, here, here, and here.

On Thursday, someone using the developer’s name took to a developer site for Ubuntu to ask that the backdoored version 5.6.1 be incorporated into production versions because it fixed bugs that caused a tool known as Valgrind to malfunction.

“This could break build scripts and test pipelines that expect specific output from Valgrind in order to pass,” the person warned, from an account that was created the same day.

One of maintainers for Fedora said Friday that the same developer approached them in recent weeks to ask that Fedora 40, a beta release, incorporate one of the backdoored utility versions.

“We even worked with him to fix the valgrind issue (which it turns out now was caused by the backdoor he had added),” the Ubuntu maintainer said.

He has been part of the xz project for two years, adding all sorts of binary test files, and with this level of sophistication, we would be suspicious of even older versions of xz until proven otherwise.

  • Cosmic ClericEnglish
    1•7 months ago

    Sorry, realize I told you I was done with our conversation, but after doing so I stumbled upon this video, and thought I would share it with you, as its pertinent to the issue we were discussing.

    You keep arguing that open source projects are strict with their code base reviews and such and are as reliable as close sourced products, and I keep seeing others saying that they are not suppliers, and everything is “as is”. We can’t both be right.

    I don’t plan on responding to you if you reply to this comment, as IMHO it would be a waste of time, as you’ll just twist this video so that its saying the opposite of what its actually saying.

    • @[email protected]English
      1•7 months ago

      You keep arguing that open source projects are strict with their code base reviews

      Go ahead and quote the words I said that suggest this. You have a talent for claiming that people have said things they have never actually said.

      The only claims I’ve made in this conversation are:

      1. The open source ecosystem does NOT strictly rely on confidence in individual project maintainers because audits and remedial measures are always possible, and done more often than most people are aware of. Of course this could and should be done more often. And maybe it would if we didn’t have so many non-contributing freeloaders in the community.
      2. Most of the widely used open source projects are not being done by hobbyists or volunteers but rather by professionals who are getting paid for their work, either via a salary or by commission as independent contractors.
      3. You don’t seem to have a firm grasp on how open source software is actually developed and managed in general.