Nix: Incorrect Behavior Order
CVE-2026-110450 is a high-severity incorrect behavior order vulnerability in Nix from NixOS, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. The record lists versions 2.28.8, 2.30.6, 2.31.6 as the first without the flaw, so updating Nix to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.15% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Nix to 2.28.8 or 2.30.6 or 2.31.6 or 2.34.9, whichever matches your release line, or a later version.
- Read the advisory on discourse.nixos.org for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| NixOS | Nix | before 2.28.8; 2.29.0 up to, but not including, 2.30.6; 2.31.0 up to, but not including, 2.31.6; 2.32.0 up to, but not including, 2.34.9; 2.35.0 up to, but not including, 2.35.3 | 2.28.8, 2.30.6, 2.31.6, 2.34.9, 2.35.3 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L. Scored by CNA (mitre.org).
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Behavior Order
The product performs multiple related behaviors, but the behaviors are performed in the wrong order in ways that may produce resultant weaknesses.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Nix
- 7.5 High severity
- 7.5 High severity
- 8.4 High severity
- 7.9 High severity
- 8.8 High severity
Recent Incorrect Behavior Order vulnerabilities
- 7.1 High severity
- 7.8 High severity
- 7.4 High severity
- 9.8 Critical severity
- 8.1 High severity
- 7.8 High severity
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