Nixos Nix vulnerabilities

CVE-2026-110453 Medium · 4.3 CWE-863 Oct 14, 2026

Incorrect Authorization in Nixos Nix

Nix before 2.35.3, when unsandboxed on macOS or FreeBSD, incorrectly allows connections made by build users from daemon clients.

CVE-2026-110452 Medium · 4.0 CWE-708 Oct 14, 2026

The multi-user installer in Nix before 2.35.3 sets the ownership of store contents to…

The multi-user installer in Nix before 2.35.3 sets the ownership of store contents to the user (who invoked the installer) even though it should be root ownership.

CVE-2026-110451 Medium · 4.3 CWE-863 Oct 14, 2026

Incorrect Authorization in Nixos Nix

Nix before 2.35.3 and Lix before 2.95.4 on macOS allow a Seatbelt sandbox escape (for an unconfined build) because a certain size threshold is mishandled.

CVE-2026-110450 High · 8.0 CWE-696 Oct 14, 2026

Nix before 2.35.3 and Lix before 2.95.4 allow privilege escalation via a repair…

Nix before 2.35.3 and Lix before 2.95.4 allow privilege escalation via a repair operation because it could destroy and then replace a store path before content verification.

CVE-2026-110449 High · 7.5 CWE-190 Oct 14, 2026

Integer Overflow or Wraparound in Nixos Nix

Nix before 2.35.3 and Lix before 2.95.4 have an integer overflow and resultant out-of-bounds write when evaluating untrusted expressions because list allocation is mishandled.

CVE-2026-64846 Low · 2.8 CWE-61 Aug 20, 2026

Nix: Arbitrary file truncation outside the sandbox with recursive-nix experimental feature

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.

CVE-2026-44029 Medium · 5.3 CWE-36 May 4, 2026

An issue was discovered in Nix before 2.34.7. Writing to arbitrary files can occur via…

An issue was discovered in Nix before 2.34.7. Writing to arbitrary files can occur via "nix-prefetch-url --unpack" or "nix store prefetch-file --unpack" directory traversal. The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 (introduced in 2.24.7);

CVE-2026-44028 High · 7.5 CWE-674 May 4, 2026

Uncontrolled Recursion in Nixos Nix

An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).

CVE-2026-39860 High · 8.4 CWE-61 Apr 8, 2026

Nix sandbox escape: file write via symlink at FOD `.tmp` copy destination

Nix is a package manager for Linux and other Unix systems. A bug in the fix for CVE-2024-27297 allowed for arbitrary overwrites of files writable by the Nix process orchestrating the builds (typically the Nix daemon running as root in multi-user installations) by following symlinks during fixed-output derivation output registration. This affects sandboxed Linux builds - sandboxed macOS builds are unaffected. The location of the temporary output used for the output copy was located inside the build chroot. A symlink, pointing to an arbitrary location in the filesystem, could be created by the derivation builder at that path. During output registration, the Nix process (running in the host mount namespace) would follow that symlink and overwrite the destination with the derivation's output contents. In multi-user installations, this allows all users able to submit builds to the Nix daemon (allowed-users - defaulting to all users) to gain root privileges by modifying sensitive files. This vulnerability is fixed in 2.34.5, 2.33.4, 2.32.7, 2.31.4, 2.30.4, 2.29.3, and 2.28.6.