CVE-2025-54800: hydra XSS — Fix

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.

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CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
nixos	hydra	< 2025-08-12

References

Advisories & Patches

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

Frequently Asked Questions

What is CVE-2025-54800? +

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. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2025-54800? +

CVE-2025-54800 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-54800? +

CVE-2025-54800 affects products from nixos, specifically: hydra. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-54800? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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