Vulnerability in Traefik

CVE-2026-48491

Traefik is an HTTP reverse proxy and load balancer. From 3.7.0 until 3.7.3, there is a high severity vulnerability in Traefik's domain-fronting protection (SNICheck) that allows an unauthenticated client to bypass mutual TLS enforced throu…

EPSS: 0.003 (20.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N.

Affected products

  • Traefik — versions >= 3.7.0, < 3.7.3

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-48491?
CVE-2026-48491 is a critical-severity vulnerability in Traefik, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 10.0/10. Published 2026-06-23.
How severe is CVE-2026-48491?
Critical severity. CVSS v3 base score is 10.0 out of 10.