CVE-2025-46416: NixOS Nix · Improper Ownership Management
Affects NixOS NixSource CVE Database V5
Not known to be exploited · CVSS 2.9 Low.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 27 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 24 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| NixOS Nix | Affected
| Fixed in– |
AI-suggested
- Upgrade to patched versions of Nix, Lix, and Guix as soon as they become available from the respective maintainers. Monitor official channels for security advisories and patches.
- Restrict local access to build environments and package managers to trusted users only, minimizing the risk of unprivileged users exploiting this vulnerability.
- Implement strict access controls and auditing on build user accounts (e.g., nixbld, guixbuild) to detect unauthorized privilege escalations.
- Use containerization or virtualization to further isolate build environments, reducing the impact of privilege escalation within the build user context.
- Employ integrity verification mechanisms such as reproducible builds and cryptographic signing of build artifacts to detect tampering.
- Regularly review and harden build environment configurations to ensure ownership and permission settings follow the principle of least privilege.
- Educate developers and build engineers about the risks of local privilege escalation and enforce policies to prevent unauthorized local access to build systems.
Description
The Nix, Lix, and Guix package managers allow a bypass of build isolation in which a user can elevate their privileges to the build user account (e.g., nixbld or guixbuild). This affects Nix through 2.24.15, 2.26.4, 2.28.4, and 2.29.1; Lix through 2.91.2, 2.92.2, and 2.93.1; and Guix before 1.4.0-38.0e79d5b.
References
- discourse.nixos.org/t/security-advisory-privilege-escalations-in-nix-lix-and-guix/66017 (opens in a new tab)
- lix.systems/blog/2025-06-24-lix-cves/ (opens in a new tab)
- guix.gnu.org/en/blog/2025/privilege-escalation-vulnerabilities-2025/ (opens in a new tab)
- labs.snyk.io (opens in a new tab)
- security.snyk.io/vuln/?search=CVE-2025-46416 (opens in a new tab)
- security-tracker.debian.org/tracker/CVE-2025-46416 (opens in a new tab)