0.0
NA
CVE-2026-64846
Nix: Arbitrary file truncation outside the sandbox with recursive-nix experimental feature
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.

INFO

Published Date :

Aug. 20, 2026, 4:18 p.m.

Last Modified :

Aug. 20, 2026, 4:18 p.m.

Remotely Exploit :

No

Source :

GitHub_M
Affected Products

The following products are affected by CVE-2026-64846 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Nixos nix
2 Nixos nix
Solution
Update Nix to version 2.35.0 or later to fix a race condition in symlink handling.
  • Update Nix to version 2.35.0 or later.
  • Disable recursive-nix experimental feature if update is not possible.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-64846 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.