CVE-2026-88007

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.0 until 2.11.57 and 3.7.13, the HTTP/3 entrypoint ConnContext does not call service.AddTransportOnContext, so kerberosRoundTripper uses a shared backend transport instead of a transport dedicated to each frontend connection. With HTTP/3 enabled, a backend using connection-bound NTLM or Negotiate authentication, and backend keep-alive, an unrelated client can reuse a backend connection authenticated for a victim, read victim-only data, and act as that victim without the victim credentials. This issue is fixed in 2.11.57 and 3.7.13.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/commit/ff39c47d7459dec9cd8de63c1a4e7aa7315bdc1c	Patch
https://github.com/traefik/traefik/pull/13812	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-qqjf-53cj-pwvv	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 15:17

Updated : 2026-09-14 19:58

NVD link : CVE-2026-88007

Mitre link : CVE-2026-88007

CVE.ORG link : CVE-2026-88007

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-287

Improper Authentication

CWE-863

Incorrect Authorization

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