High severity · published Oct 22, 2026
CVE-2026-114642
Traefik before 2.11.58 and 3.7.14 TLS Config Bypass via NTLM/Kerberos Round Tripper
New
8.7
CVSS
0.2%
EPSS
No
On KEV
Description
Traefik 2.11.0 before 2.11.58 and 3.0.0 before 3.7.14 stores its NTLM/Kerberos backend round tripper in a client-connection slot not keyed by ServersTransport, so one service's TLS client configuration is reused for another service's backend. An unauthenticated client can arm the slot via a backend issuing an NTLM or Negotiate challenge, then reach another service on the same keep-alive connection, bypassing its root CAs, server name, and certificate verification.
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
2.11.0 before 2.11.58; 3.0.0 before 3.7.14 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-114642
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-114642
Vendor Advisory
https://github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp
Third Party Advisory
https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypass-via-ntlm-kerberos-round-tripper
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