CVE-2026-71326

Summary

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.

Affected Software

VendorProductVersion RangeStatus
traefiktraefik>= 3.6.11, < 3.6.25affected
traefiktraefik>= 3.7.0, < 3.7.10affected

Weaknesses

  • CWE-287: CWE-287: Improper Authentication

References