CVE-2026-64846

Published Aug 20, 2026

Last updated 4 days ago

Overview

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.
Source
security-advisories@github.com
NVD status
Received

Risk scores

CVSS 3.1

Type
Secondary
Base score
2.8
Impact score
1.4
Exploitability score
1.1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N
Severity
LOW

Weaknesses

security-advisories@github.com
CWE-61

Social media

Hype score
Not currently trending