CVE-2026-112778
Traefik before 2.11.46, 3.6.17, and 3.7.1 Cross-Namespace Resource Reference via Kubernetes Annotations
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Traefik before 2.11.46, 3.6.17, and 3.7.1 Cross-Namespace Resource Reference via Kubernetes Annotations
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
- Record
CVE-2026-112778- CVSS 4.0
- 6.4 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H - Weakness
- CWE-862
- Updated
- 2026-11-02
EUVDEUVD-2026-104584
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
- Record
EUVD-2026-104584- CVSS 4.0
- 6.4 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-35mp-944w-x8rj
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and...
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
- Record
GHSA-35mp-944w-x8rj- CVSS 4.0
- 6.4 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H/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 - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-862
- Updated
- 2026-11-02
NVD
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
- Record
CVE-2026-112778- CVSS 4.0
- 6.4 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H/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 - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-862
- Updated
- 2026-11-02
OSV
Traefik before 2.11.46, 3.6.17, and 3.7.1 Cross-Namespace Resource Reference via Kubernetes Annotations
Traefik before 2.11.46, 3.x before 3.6.17, and 3.7.0 lack namespace validation for Ingress and Service annotations in the Kubernetes Ingress provider, allowing references to Middlewares, ServersTransports, and TLSOptions in other namespaces. Attackers able to create or update Ingress or Service resources in one namespace can set router.middlewares or service.serverstransport annotations to obtain another tenant's injected credentials or reuse its client certificates, bypassing namespace-based tenant isolation.
- Record
CVE-2026-112778- CVSS 4.0
- 6.4 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:H - Weakness
- CWE-862
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-112778 is a medium vulnerability (CVSS 6.4) in Traefik, published October 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.20%, the 10th percentile. No source names a fixed version.
References
github.com/traefik/traefik/security/advisories/GHSA-rh7m-2m44-x32f
vulncheck.com/advisories/traefik-before-2.11.46-3.6.17-and-3.7.1-cross-namespace-resource-reference-via-kubernetes-annotations
nvd.nist.gov/vuln/detail/CVE-2026-112778