Vulnerability · Published Aug 12, 2025 · Assigned by GitHub_M

CVE-2025-54800Hydra persistent XSS in build metrics

High 7.1

In plain English

A high-severity cross-site scripting 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 0.2% (higher than 12% of all known vulnerabilities).

Severity (CVSS 4.0)7.1High

Exploit odds (30 days)0.2%top 88.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Hydra is a continuous integration service for Nix based projects. Prior to commit dea1e16, a malicious package can introduce arbitrary JavaScript code into the Hydra database that is automatically evaluated in a client's browser when anyone visits the build page. This could be done by a third-party project as part of its build process. This also happens in other places like with hydra-release-name. This issue has been patched by commit dea1e16. A workaround involves either not building untrusted packages or not visiting the builds page.

Affected products (as reported)

Vendor	Product	Versions
NixOS	hydra	< dea1e168f590efb27db32dbacc82b09e15f8ae4b

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N

References

https://github.com/NixOS/hydra/security/advisories/GHSA-7qwg-q53v-vh99 x_refsource_CONFIRM
https://github.com/NixOS/hydra/commit/dea1e168f590efb27db32dbacc82b09e15f8ae4b x_refsource_MISC