{"schemaVersion":3,"id":"CVE-2026-64846","aliases":["UBUNTU-CVE-2026-64846","DEBIAN-CVE-2026-64846"],"status":"published","duplicateOf":null,"title":null,"description":"Nix is a package manager for Linux and other Unix systems. Prior to 2.35.0, a malicious derivation executed with the recursive-nix experimental feature can exploit a time-of-check/time-of-use race involving final symlink handling in the LocalStore restore path. The race can cause writeFile to follow a substituted final symlink when opening a path with O_TRUNC instead of enforcing FinalSymlink::DontFollow, allowing the Nix process or nix-daemon to create or truncate an empty file outside the build sandbox with the daemon user's permissions. The primitive does not provide arbitrary-content writes and requires winning the race. This issue is fixed in version 2.35.0.","dates":{"published":"2026-08-20T16:18:06.729Z","modified":"2026-08-20T19:32:22.878Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":2.8,"severity":"low","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":2.8,"severity":"low","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":2.8,"severity":"low","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N","exploitability":2.8,"impact":2.3,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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