Vulnerability · Published Apr 22, 2024 · Assigned by GitHub_M

CVE-2024-32657Hydra has persistent XSS vulnerability serving HTML build outputs

Medium 4.6

In plain English

A medium-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 0.5% (higher than 41% of all known vulnerabilities).

Severity (CVSS 3.1)4.6Medium

Exploit odds (30 days)0.5%top 59.4% 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. Attackers can execute arbitrary code in the browser context of Hydra and execute authenticated HTTP requests. The abused feature allows Nix builds to specify files that Hydra serves to clients. One use of this functionality is serving NixOS `.iso` files. The issue is only with html files served by Hydra. The issue has been patched on https://hydra.nixos.org around 2024-04-21 14:30 UTC. The nixpkgs package were fixed in unstable and 23.11. Users with custom Hydra packages can apply the fix commit to their local installations. The vulnerability is only triggered when opening HTML build artifacts, so not opening them until the vulnerability is fixed works around the issue.

Affected products (as reported)

Vendor	Product	Versions
NixOS	hydra	< b72528be5074f3e62e9ae2c2ae8ef9c07a0b4dd3< 23.11

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

References

https://github.com/NixOS/hydra/security/advisories/GHSA-2p75-6g9f-pqgx x_refsource_CONFIRM
https://github.com/NixOS/nixpkgs/pull/306017 x_refsource_MISC
https://github.com/NixOS/nixpkgs/pull/306018 x_refsource_MISC
https://github.com/NixOS/hydra/commit/b72528be5074f3e62e9ae2c2ae8ef9c07a0b4dd3 x_refsource_MISC