DescriptionNix is a package manager for Linux and other Unix systems. A fixed-output derivations on Linux can send file descriptors to files in the Nix store to another program running on the host (or another fixed-output derivation) via Unix domain sockets in the abstract namespace. This allows to modify the output of the derivation, after Nix has registered the path as "valid" and immutable in the Nix database. In particular, this allows the output of fixed-output derivations to be modified from their expected content. This issue has been addressed in versions 2.3.18 2.18.2 2.19.4 and 2.20.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs1066113, 1066812

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
guix (PTS)bullseye1.2.0-4+deb11u1vulnerable
sid, trixie1.4.0-6fixed
nix (PTS)bullseye2.3.7+dfsg1-1vulnerable
sid, trixie2.18.1+dfsg-1vulnerable

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs


[bookworm] - guix <no-dsa> (Minor issue)
[bullseye] - guix <no-dsa> (Minor issue)
[bookworm] - nix <no-dsa> (Minor issue)
[bullseye] - nix <no-dsa> (Minor issue)
Fixed by:

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