Description
Traefik before v2.11.58 and v3.7.14 contains an authentication bypass vulnerability in its SNI check, which is skipped when request TLS state is nil. Unauthenticated clients can send HTTP/2 requests with the :scheme http pseudo-header over TLS on Go 1.27 builds to reach routers requiring client certificates without presenting one.
Affected products
traefik: traefik
References2
- github.com/traefik/traefik/security/advisories/GHSA-fh26-gfpp-7… Vendor Advisory
- www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-… Third Party Advisory
Metrics
- CVSS 3.1
-
8.7
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N - CVSS 4.0
-
7.0
HIGH
Score source: CNA
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/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 - EPSS — exploit probability
- 0% percentile: 8 · as of 8 November 2026
- CWE
- CWE-288
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.