CVE-2022-23632

The Silent Fallback: Bypassing Traefik mTLS with CVE-2022-23632

Amit Schendel
Amit Schendel
Senior Security Researcher

Jan 12, 2026·6 min read·0 visits

Executive Summary (TL;DR)

Traefik versions prior to 2.6.1 fail to apply specific TLS configurations (like mTLS enforcement) when handling certain FQDN requests. The system defaults to the global TLS config, which is often less secure. If your default config doesn't require client certificates, an attacker can bypass authentication entirely by simply asking nicely.

A logic flaw in Traefik's TLS configuration selection allows attackers to bypass router-specific security settings, including Mutual TLS (mTLS) requirements, by forcing a fallback to the default configuration.

Fix Analysis (1)

Technical Appendix

CVSS Score
7.4/ 10
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Probability
0.56%
Top 32% most exploited

Affected Systems

Traefik < 2.6.1Oracle Communications Unified Inventory Management 7.5.0Oracle Communications Order and Service Management 7.4.0Oracle Communications Order and Service Management 7.4.1

Affected Versions Detail

Product
Affected Versions
Fixed Version
Traefik
Traefik Labs
< 2.6.12.6.1
Unified Inventory Management
Oracle
7.5.0See Vendor Advisory
AttributeDetail
Attack VectorNetwork (AV:N)
CVSS v3.17.4 (High)
ImpactSecurity Bypass / Info Disclosure
EPSS Score0.56%
Exploit StatusPoC Available
KEV StatusNot Listed
CWE-295
Improper Certificate Validation

Improper Validation of Certificate with Host Mismatch

Vulnerability Timeline

Vulnerability Disclosed & Patch Prepared
2022-02-14
Traefik v2.6.1 Released (Fix)
2022-02-17
CVE-2022-23632 Published
2022-02-17
Oracle Advisory (July CPU)
2022-07-19

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