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•8 months ago

    internally they are generally lazy and do the bare minimum.

    Day to day, and with a lazy manager who is not technically knowledgeable, I would agree, and they do existence in corporations.

    But if you work for one who knows what they’re doing and gets a mandate from their boss to make sure the code doesn’t leave the corporation legally exposed, then not so much.

    Also special events like Y2K also gets extra scrutiny for legal reasons way up and above the normal level scrutiny thing production code gets.

    I’ve worked it both types throughout my career.

    • @[email protected]English
      2•8 months ago

      The same argument can be made about open source, some projects are very carefully and festidously managed, and others not so much.

      Main difference is with closed source, it’s hard to know which sort of situation your are dealing with, and no option for an interested third party to come along and fix a problematic project.