Koa Vulnerable to Open Redirect via Trailing Double-Slash (//) in back Redirect Logic (koajs koa)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.29 % · percentile 22 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
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 functionality. In certain circumstances, an attacker can manipulate the Referer header to force a user’s browser to navigate to an external, potentially malicious website. This occurs because the implementation incorrectly treats some specially crafted URLs as safe relative paths. Exploiting this vulnerability could allow attackers to perform phishing, social engineering, or other redirect-based attacks on users of affected applications. This issue has been patched in version 3.0.3.
Weaknesses (CWE)
- CWE-601 — URL Redirection to Untrusted Site
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N | GitHub_M |
| CVSS 3.1 | MEDIUM 4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | MEDIUM 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N | NVD · nvd@nist.gov (Primary) |
Advisories
- GHSA-g8mr-fgfg-5qpc — Koa Vulnerable to Open Redirect via Trailing Double-Slash (//) in back Redirect Logic
European references
- ENISA EUVD · EUVD-2025-35182
- GCVE · GCVE-0-2025-62595
Affected configurations (NVD CPE)
cpe:2.3:a:koajs:koa:*:*:*:*:*:node.js:*:*≥ 3.0.1 < 3.0.3cpe:2.3:a:koajs:koa:2.16.2:*:*:*:*:node.js:*:*
Affected products
| Product | Versions |
|---|---|
| koajs · koa | affected >= 2.16.2, < 2.16.3 ; affected >= 3.0.1, < 3.0.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |