CVE-2026-85597 (GCVE-0-2026-85597)
Vulnerability from cvelistv5 – Published: 2026-09-04 11:30 – Updated: 2026-10-08 15:51
VLAI
EPSS
VEX
Title
Traefik before v2.11.55 and v3.0.0 through v3.7.10 mTLS Bypass via TLS Option Conflict
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 18:03 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/traefik/traefik/security/advis… | vendor-advisory |
| https://www.vulncheck.com/advisories/traefik-befo… | third-party-advisory |
Impacted products
Date Public
2026-08-21 00:00
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