Vulnerability · Published Aug 12, 2025 · Assigned by GitHub_M
CVE-2025-54864Hydra missing authentication when triggering evaluations through GitHub and Gitea plugins
Medium 6.9
In plain English
A medium-severity missing authentication in hydra from NixOS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities).
Official description
Hydra is a continuous integration service for Nix based projects. Prior to commit f7bda02, /api/push-github and /api/push-gitea are called by the corresponding forge without HTTP Basic authentication. Both forges do however feature HMAC signing with a secret key. Triggering an evaluation can be very taxing on the infrastructure when large evaluations are done, introducing potential denial of service attacks on the host running the evaluator. This issue has been patched by commit f7bda02. A workaround involves blocking /api/push-github and /api/push-gitea via a reverse proxy.
Affected products (as reported)
Weakness: CWE-306 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/NixOS/hydra/security/advisories/GHSA-qpq3-646c-vgx9 x_refsource_CONFIRM
- https://github.com/NixOS/hydra/commit/f7bda020c6144913f134ec616783e57817f7686f x_refsource_MISC