CVE-2026-32305
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
CVSS
5.3
Medium
EPSS
0.4%
p33
KEV
—
Exploit Today
10
0-100
Published: Mar 20, 2026 · Last modified: Jul 15, 2026 · CWE-287 · CWE-1188 · CWE-179
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.
- github.comhttps://github.com/traefik/traefik/releases/tag/v2.11.41
- github.comhttps://github.com/traefik/traefik/releases/tag/v3.6.11
- github.comhttps://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2
- github.comhttps://github.com/traefik/traefik/security/advisories/GHSA-wvvq-wgcr-9q48
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:10175
- access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:21772
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-32305
- bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2449595
- security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32305.json