CVE-2026-55602

http-proxy-middleware is node.js http-proxy middleware. From 0.16.0 until 2.0.10, 3.0.6, and 4.1.0, http-proxy-middleware documents router proxy-table entries as host, path, or host+path selectors, but the host+path implementation uses unanchored substring matching on attacker-controlled request metadata. As a result, a crafted Host header that is only a superstring match for a configured host+path key can still route a request to an unintended backend. This vulnerability is fixed in 2.0.10, 3.0.6, and 4.1.0.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj	Exploit Vendor Advisory
https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:chimurai:http-proxy-middleware::::::::
	cpe:2.3:a:chimurai:http-proxy-middleware::::::::
	cpe:2.3:a:chimurai:http-proxy-middleware::::::::

History

26 Jun 2026, 20:06

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.6
References	~~() https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj -~~	() https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj - Exploit, Vendor Advisory
First Time		Chimurai Chimurai http-proxy-middleware
CPE		cpe:2.3:a:chimurai:http-proxy-middleware::::::::

23 Jun 2026, 15:16

Type	Values Removed	Values Added
References	~~() https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj -~~	() https://github.com/chimurai/http-proxy-middleware/security/advisories/GHSA-64mm-vxmg-q3vj -

22 Jun 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 18:16

Updated : 2026-06-26 20:06

NVD link : CVE-2026-55602

Mitre link : CVE-2026-55602

CVE.ORG link : CVE-2026-55602

JSON object : View

Products Affected

chimurai

http-proxy-middleware

CWE

CWE-20

Improper Input Validation

CWE-187

Partial String Comparison

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