CVE-2026-88009

Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sanitization, forwardAuth, encodedCharacters, and access logging against a path normalized to / but forwards URL.Opaque verbatim to the backend, allowing cross-vhost routing bypass, path-scoped authorization bypass, and access-log evasion when the backend interprets the opaque target as a path. This issue is fixed in 2.11.57 and 3.7.13.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/commit/58d1e9ca204526823211e30fd4634101c59d58e9	Patch
https://github.com/traefik/traefik/pull/13796	Issue Tracking Patch
https://github.com/traefik/traefik/releases/tag/v2.11.57	Release Notes
https://github.com/traefik/traefik/releases/tag/v3.7.13	Release Notes
https://github.com/traefik/traefik/security/advisories/GHSA-f52w-8j3h-j724	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:traefik:traefik::::::::
	cpe:2.3:a:traefik:traefik::::::::

History

No history.

Information

Published : 2026-09-10 16:18

Updated : 2026-09-14 19:59

NVD link : CVE-2026-88009

Mitre link : CVE-2026-88009

CVE.ORG link : CVE-2026-88009

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CWE-1286

Improper Validation of Syntactic Correctness of Input

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