CVE-2026-71326

Traefik is an open source HTTP reverse proxy and load balancer. From 3.6.11 until 3.6.25 and 3.7.10, Traefik's BasicAuth middleware in pkg/middlewares/auth/basic_auth.go deduplicates concurrent password checks with a singleflight key built from the delimiter-free concatenation of password and secret, allowing an attacker who has a valid credential and the stored hash to authenticate as an unconfigured username when headerField trusts the forwarded identity. This issue is fixed in 3.6.25 and 3.7.10.

CVSS

No CVSS.

References

Link	Resource
https://github.com/traefik/traefik/commit/b5ace8eb5d6779980567f5e75efd2d9e08b7e350
https://github.com/traefik/traefik/pull/13572
https://github.com/traefik/traefik/releases/tag/v3.6.25
https://github.com/traefik/traefik/releases/tag/v3.7.10
https://github.com/traefik/traefik/security/advisories/GHSA-6765-c87h-8mrf

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-06 22:18

Updated : 2026-09-08 20:53

NVD link : CVE-2026-71326

Mitre link : CVE-2026-71326

CVE.ORG link : CVE-2026-71326

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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