CVE-2026-85597

HIGH CVSS 4.0: 8.2 EPSS 0.23%
Updated Sep 08, 2026
Traefik
Parameter Value
CVSS 8.2 (HIGH)
Affected Versions 3.0.0 — 3.7.12
Fixed In 2.11.55
Type CWE-863 (Incorrect Authorization)
Vendor Traefik
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption

CVSS Vector v4.0

Vulnerable Products 2

Configuration From (including) Up to (excluding)
Traefik Traefik
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
2.11.55
Traefik Traefik
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
3.0.0 <= 3.7.12