Open Redirect in Koajs Koa

CVE-2025-62595

Koa is expressive middleware for Node.js using ES2017 async functions. In versions 2.16.2 to before 2.16.3 and 3.0.1 to before 3.0.3, a bypass to CVE-2025-8129 was discovered in the Koa.js framework affecting its back redirect functionalit…

Vulnerability class: Open Redirect

EPSS: 0.003 (19.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

Affected products

  • Koajs Koa — versions >= 2.16.2, < 2.16.3, >= 3.0.1, < 3.0.3, 2.16.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-62595?
CVE-2025-62595 is a medium-severity vulnerability in Koajs Koa, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 4.3/10. Published 2025-10-21.
How severe is CVE-2025-62595?
Medium severity. CVSS v3 base score is 4.3 out of 10.