CVE
CVE-2026-53622
Traefik: HTTP/3 mTLS bypass via exact SNI TLSOptions lookup for wildcard and mixed-case hosts in github.com/traefik/traefik
Traefik's HTTP/3 TLS configuration selection is vulnerable to a bypass when using wildcard or mixed-case hosts in the SNI.
The HTTP/3 (QUIC) path performed a direct, case-sensitive lookup on the SNI value to select the applicable TLS configuration. This lookup failed to match wildcard host patterns (e.g., "*.example.com") or case variants of configured hostnames. In these cases, Traefik would fall back to the default TLS configuration, which might not enforce mutual TLS (mTLS), allowing unauthenticated clients to access protected backends.
Package Versions Affected
Package Version
patch Availability
No items found.
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
7.8
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
9.1
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Related Resources
No items found.
References
https://github.com/traefik/traefik/security/advisories/GHSA-9cr8-q42q-g8m7, https://github.com/traefik/traefik/releases/tag/v3.7.3