CVE-2026-11311 F5 CVE debrief

Who should care

NGINX Gateway Fabric users and administrators should be aware of this vulnerability and take necessary actions to mitigate it. This includes reviewing NGINX configurations, implementing additional security controls, and applying vendor-provided patches or updates. Affected operators, platforms, vulnerability-management teams, and security teams should prioritize this vulnerability based on their specific exposure and risk.

Technical summary

The vulnerability exists in the NGINX configuration generator component of NGINX Gateway Fabric. User-supplied string values from the NginxProxy Custom Resource Definition serverTokens field and the AuthenticationFilter Custom Resource Definition extraAuthArgs field are rendered directly into NGINX configuration templates without sanitization or escaping. This allows an authenticated attacker with permission to create or modify these Custom Resource Definitions to craft values that inject arbitrary NGINX configuration directives.

Defensive priority

High

Recommended defensive actions

• Review and update NGINX Gateway Fabric configurations to ensure proper sanitization and escaping of user-supplied string values.
• Implement additional security controls to monitor and restrict modifications to Custom Resource Definitions.
• Apply vendor-provided patches or updates to address the vulnerability.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record was published on 2026-06-17T15:16:42.617Z and was last modified on 2026-07-02T20:01:39.157Z. The NVD entry is currently Analyzed. This information is based on the supplied source corpus. Defenders should verify the accuracy of this information within the context of their specific environment and review the official CVE record and NVD entry for further details.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.