Disclosed backdoor in xz releases - FreeBSD not affected

FreeBSD is not affected by the recently announced backdoor included in the 5.6.0 and 5.6.1 xz releases.

All supported FreeBSD releases include versions of xz that predate the affected releases.

The main, stable/14, and stable/13 branches do include the affected version (5.6.0), but the backdoor components were excluded from the vendor import. Additionally, FreeBSD does not use the upstream's build tooling, which was a required part of the attack. Lastly, the attack specifically targeted x86_64 Linux systems using glibc.

The FreeBSD ports collection does not include xz/liblzma.

Reference:
https://www.openwall.com/lists/oss-security/2024/03/29/4

Best regards,
Gordon Tetlow
Hat: security-officer