CVE-2026-85597
Published:September 04, 2026
Updated:September 22, 2026
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.
Affected Packages
https://github.com/traefik/traefik.git (GITHUB):
Affected version(s) >=v2.0.0 <v2.11.55Fix Suggestion:
Update to version v2.11.55https://github.com/traefik/traefik.git (GITHUB):
Affected version(s) >=v3.0.0 <v3.7.11Fix Suggestion:
Update to version v3.7.11github.com/traefik/traefik/v2 (GO):
Affected version(s) >=v2.0.0 <v2.11.55Fix Suggestion:
Update to version v2.11.55github.com/traefik/traefik/v3 (GO):
Affected version(s) >=v3.0.0 <v3.7.11Fix Suggestion:
Update to version v3.7.11Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.2
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Incorrect Authorization
EPSS
Base Score:
0.21