Yesterday we learned of a supply chain back door in the xz-utils software via an announcement at The vulnerability was distributed with versions 5.6.0 and 5.6.1 of xz; and has been assigned CVE-2024-3094.

OmniOS is NOT affected by CVE-2024-3094

The malicious code is only present in binary artefacts if the build system is Linux (and there are some additional constraints too) and if the system linker is GNU ld – neither of which are true for our packages. The payload is also a Linux ELF binary which would not successfully link into code built for OmniOS, and requires features which are only present in the GNU libc.

We have also only ever shipped xz-utils 5.6.x as part of the unstable bloody testing release, stable releases contain older versions:

  • r151038 ships version 5.2.6
  • r151046 ships version 5.4.2
  • r151048 ships version 5.4.4
  • bloody ships version 5.6.1

Despite being unaffected, we have now switched builds of xz in bloody to using the raw source archive, which does not contain the malicious injection code, and generating the autoconf files ourselves. We have not downgraded to an earlier version as it is not clear which earlier version can be considered completely safe given that the perpetrator has been responsible for maintaining and signing releases back to version 5.4.3. Once a cleaned 5.6.2 release is available, we will upgrade to that.

Any problems or questions, please get in touch.