CVE-2026-114656
Traefik before 2.11.58 and 3.7.13 contains an authentication bypass vulnerability that allows unauthenticated clients to skip client-certificate checks because negated Host matchers are counted as served domains. Attackers can reach backends protected by RequireAndVerifyClientCert when a router rule with !Host() creates a TLS options conflict that falls back to the default options.
Executive briefing
This record describes a reported software or hardware weakness. The description and CVSS rating are source metadata; practical risk depends on whether your environment uses an affected product/version and whether the vulnerable component is reachable and configured in an exploitable way.
Severity & exploitability
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Impacted products and platforms
Affected product configuration identifiers from NVD. Confirm exact versions and platform applicability against the vendor advisory.
| Product / CPE identifier | Version range | Vulnerable match |
|---|---|---|
cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* | 3.0.0 – 3.7.13 | Yes |
How it works and what it could affect
The NVD description is the authoritative short summary currently available for this record. A detailed technical mechanism is not inferred when the source record does not provide one.
Weakness classification: CWE-436
Review the CVSS attack characteristics above to understand whether exploitation is network/local, whether privileges or user interaction are required, and which confidentiality, integrity or availability impacts are scored.
Remediation and recommended response
- Identify exposure: compare the affected product and version ranges below with your asset inventory, software bill of materials, endpoint inventory and externally exposed services.
- Remediate: review the linked vendor security advisory or patch notes, upgrade to a fixed release, or apply the vendor-provided workaround if an upgrade cannot be completed.
- Mitigate while patching: restrict network access to the vulnerable service, disable the affected feature where operationally safe, and monitor vendor/CERT advisories for updated guidance.
- Validate: confirm the fixed version or mitigation on representative systems, run a vulnerability rescan, and retain change evidence.
Vendor remediation / security advisories
Exploit intelligence & references
No CISA KEV match is recorded in the latest successful catalog refresh. This is not a guarantee that public proof-of-concept code or exploitation does not exist.
- disclosure@vulncheck.com patch
- disclosure@vulncheck.com advisory
Sources: NVD and CISA KEV when available. Vendor confirmation remains the final authority for fixed versions and workarounds.