CVE-2026-77180 PUBLISHED

NGINX Ingress Controller vulnerability

Assigner: f5
Reserved: 20.08.2026 Published: 02.09.2026 Updated: 02.09.2026

When NGINX Ingress Controller is configured with Ingress annotations, an injection vulnerability exists in the configuration generator of NGINX Ingress Controller. Multiple user-controllable fields are written into the generated NGINX configuration without sanitization. An authenticated attacker with permission to create or modify these annotations may craft values that inject arbitrary NGINX configuration directives.

Impact: An authenticated attacker granted write access to NGINX Ingress Controller Ingress annotations through the Kubernetes API may be able to inject arbitrary NGINX configuration directives, create or delete files, or disable services. There is no data plane exposure; this is a control plane issue only.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N
CVSS Score: 8.7

Product Status

Vendor F5
Product NGINX Ingress Controller
Versions Default: unknown
  • affected from 5.0.0 to 5.6.0 (excl.)
  • affected from 2026-lts-r1 to 2026-lts-r5 (excl.)

Workarounds

  • Restrict Kubernetes Role-based Access Control (RBAC) create, update, and patch permissions on VirtualServer, VirtualServerRoute, Policy, DosProtectedResource, and Ingress resources to trusted cluster administrators only.
  • Deploy an admission policy (Kyverno, OPA Gatekeeper, or ValidatingAdmissionPolicy) that rejects resources containing special characters in user-controlled fields.

Credits

  • F5 acknowledges kodareef5 for bringing this issue to our attention and following the highest standards of coordinated disclosure. reporter

References

Problem Types

  • CWE-76 Improper Neutralization of Equivalent Special Elements CWE