CVE-2025-62595

4.3 MEDIUM
Published: October 21, 2025 Modified: January 20, 2026
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc
Source: security-advisories@github.com
Exploit Vendor Advisory
https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Exploit Vendor Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
4.3 / 10.0
EPSS (Exploit Probability)
0.0%
1th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

koajs