CVE-2026-32305
HIGH EPSS 22.2%
Published Mar 20, 20263mo ago · Modified Jun 17, 20261w ago
7.8 CVSS 4.0
Published Mar 20, 2026 3mo ago
Last Modified Jun 17, 2026 1w ago
Description
Traefik is an HTTP reverse proxy and load balancer. Versions 2.11.40 and below, 3.0.0-beta1 through 3.6.11, and 3.7.0-ea.1 are vulnerable to mTLS bypass through the TLS SNI pre-sniffing logic related to fragmented ClientHello packets. When a TLS ClientHello is fragmented across multiple records, Traefik's SNI extraction may fail with an EOF and return an empty SNI. The TCP router then falls back to the default TLS configuration, which does not require client certificates by default. This allows an attacker to bypass route-level mTLS enforcement and access services that should require mutual TLS authentication. This issue is patched in versions 2.11.41, 3.6.11 and 3.7.0-ea.2.
CVSS Details
Base Score
Exploitability
Impact
Vector string
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 Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
22.2% percentile
Exploit & Patch Status
No Known Exploit
Patch Available
Weaknesses 2
CWE-1188
CWE-287 Improper Authentication Authentication
Affected Products 3
References 4
- github.com https://github.com/traefik/traefik/releases/tag/v2.11.41
- github.com https://github.com/traefik/traefik/releases/tag/v3.6.11
- github.com https://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2
- github.com https://github.com/traefik/traefik/security/advisories/GHSA-wvvq-wgcr-9q48
Remediation
- github.com https://github.com/traefik/traefik/security/advisories/GHSA-wvvq-wgcr-9q48