CVE-2025-8129: Koajs Koa

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability, which was classified as problematic, was found in KoaJS Koa up to 3.0.0. Affected is the function back in the library lib/response.js of the component HTTP Header Handler. The manipulation of the argument Referrer leads to open redirect. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used.

Affected products

• Koajs Koa: from 2.0.0, before 2.16.2 (fixed in 2.16.2); version 3.0.0 only

Published 2025-07-25. Last modified 2026-06-17.