RCE in Nixos Hydra
CVE-2025-32435
Hydra is a Continuous Integration service for Nix based projects. Evaluation of untrusted non-flake nix code could potentially access secrets that are accessible by the hydra user/group. This should not affect the signing keys, that are owned by the hydra-queue-runner and hydra-www users respectively.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 2.6 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 21.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
- Nixos Hydra — versions < 8d750265135b7e203520036a742afdf301b4013f
Weakness classification (CWE)
References
- github.com/NixOS/hydra/security/advisories/GHSA-j7w7-965w-vjxw (Vendor Advisory)
- github.com/NixOS/nixpkgs/pull/397919 (Issue Tracking)
- github.com/NixOS/hydra/commit/8d750265135b7e203520036a742afdf301b4013f (Patch)
- github.com/nix-community/nix-eval-jobs/releases/tag/v2.28.1 (Release Notes)
Frequently asked questions
- What is CVE-2025-32435?
- CVE-2025-32435 is a low-severity vulnerability in Nixos Hydra, classified under Eval Injection. CVSS score: 2.6/10. Published 2025-04-15.
- How severe is CVE-2025-32435?
- Low severity. CVSS v3 base score is 2.6 out of 10.