CVE-2026-65600

Traefik versions <= v2.11.51, >= v3.6.0 <= v3.6.22, and >= v3.7.0 <= v3.7.6 contain an authentication bypass via path traversal in the ReplacePathRegex middleware. When ReplacePathRegex is configured with a regex that captures user-controlled path segments without a mandatory path separator (e.g. regex "^/api(.*)", replacement "/$1"), the middleware forwards the replaced path to the backend without validating that it matches its normalized form. An unauthenticated remote attacker can send a crafted request (e.g. GET /api../admin) that produces an un-normalized path such as /../admin, which a backend that normalizes paths resolves to a protected route, bypassing authentication middleware. Fixed in v2.11.52, v3.6.23, and v3.7.7.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/security/advisories/GHSA-cxjq-mrr5-89rv	Vendor Advisory Patch
https://www.vulncheck.com/advisories/traefik-before-authentication-bypass-via-replacepathregex	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:traefik:traefik::::::::
	cpe:2.3:a:traefik:traefik::-::::::*
	cpe:2.3:a:traefik:traefik::-::::::*

History

No history.

Information

Published : 2026-07-22 12:18

Updated : 2026-08-06 15:42

NVD link : CVE-2026-65600

Mitre link : CVE-2026-65600

CVE.ORG link : CVE-2026-65600

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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