High severity · published Oct 22, 2026
CVE-2026-114640
Traefik v3.7.0 before v3.7.14 mTLS Header Spoofing via Ingress-NGINX HTTP Router
New
8.7
CVSS
0.2%
EPSS
No
On KEV
Description
Traefik from v3.7.0 before v3.7.14 contains an authentication bypass vulnerability in its Kubernetes Ingress-NGINX provider that forwards client-supplied Ssl-Client-* headers on the plaintext HTTP router. When ssl-redirect is disabled alongside auth-tls-pass-certificate-to-upstream, unauthenticated attackers can send Ssl-Client-Verify: SUCCESS with a chosen certificate subject and issuer to impersonate mTLS identities.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TR
traefik · traefik
3.7.0 before 3.7.14 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-114640
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-114640
Vendor Advisory
https://github.com/traefik/traefik/security/advisories/GHSA-mwrr-6hp4-pxr6
Third Party Advisory
https://www.vulncheck.com/advisories/traefik-3.7.0-before-3.7.14-mtls-header-spoofing-via-ingress-nginx-http-router
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