CVE-2026-85597
High
High exploit probability or critical severity with a known exploit.
CVSS base
9.1
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS — probability of exploitation (30 days)
0.2%
10.8th percentile
CISA KEV
Not listed
Weakness / dates
CWE-863
Published 2026-09-04 · modified 2026-09-16
Description
Traefik before v2.11.55 and v3.0.0 through v3.7.10 contain a TLS option conflict resolution vulnerability that allows unauthenticated attackers to bypass client-certificate authentication by creating conflicting TLS options on multi-host routers. Attackers can reach protected backends by exploiting shared TLS resolution across multiple hostnames in a single router rule, causing the strict mTLS requirement to fall back to default options for all hosts.