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 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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/koajs/koa/commit/769fd75cc6b30d72493b370b5a3ae2332ca03c5b	Patch
https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc	Exploit Vendor Advisory
https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:koajs:koa::::::node.js::*
	cpe:2.3:a:koajs:koa:2.16.2:::::node.js::

History

20 Jan 2026, 14:45

Type	Values Removed	Values Added
First Time		Koajs koa Koajs
CPE		cpe:2.3:a:koajs:koa:2.16.2:::::node.js:: cpe:2.3:a:koajs:koa::::::node.js::*
References	~~() https://github.com/koajs/koa/commit/769fd75cc6b30d72493b370b5a3ae2332ca03c5b -~~	() https://github.com/koajs/koa/commit/769fd75cc6b30d72493b370b5a3ae2332ca03c5b - Patch
References	~~() https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc -~~	() https://github.com/koajs/koa/security/advisories/GHSA-g8mr-fgfg-5qpc - Exploit, Vendor Advisory

21 Oct 2025, 17:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-10-21 17:15

Updated : 2026-01-20 14:45

NVD link : CVE-2025-62595

Mitre link : CVE-2025-62595

CVE.ORG link : CVE-2025-62595

JSON object : View

Products Affected

koajs

koa

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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