CVE-2026-121966highCWE-488

CVE-2026-121966: high-severity vulnerability in traefik

Traefik before 2.11.60 and 3.7.16 ForwardAuth NTLM/Negotiate Identity Leak

Published

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

18Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7
Traefik 2.x before 2.11.60 and 3.x before 3.7.16 sends ForwardAuth subrequests (and, in 3.7, Ingress NGINX auth-url requests) through an auth-server connection pool shared by all clients, exposing connection-bound NTLM or Negotiate authentication. An unauthenticated attacker can reuse another user's authenticated connection, receiving the victim's identity via authResponseHeaders to access backends as that user.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
Affected products
traefik · traefik