Configuration injection in ingress-nginx auth-tls-match-cn annotation
CVE-2025-1097 is an input-validation vulnerability in the Kubernetes ingress-nginx controller. Improper sanitization of the auth-tls-match-cn Ingress annotation allows an attacker to inject malicious NGINX configuration. Exploitation can lead to arbitrary code execution in the controller's context and disclosure of Kubernetes Secrets accessible to its service account. Default installations grant the controller access to Secrets cluster-wide. Fixed releases are 1.11.5 and 1.12.1.
What it means and what to do now: patch path, interim mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
Successful exploitation can compromise the ingress-nginx controller through arbitrary code execution and expose Secrets within its authorization scope. In default installations, this includes Secrets across the cluster. Exposure of credentials and service account tokens can enable further privilege escalation and potentially cluster takeover, depending on the permissions associated with those credentials.
If you can’t patch tonight, do this now.
Restrict use of vulnerable Ingress annotations and increase monitoring of ingress-nginx activity. To reduce exposure to the unauthenticated admission-webhook exploitation chain involving CVE-2025-1974, temporarily disable the Validating Admission Controller or restrict network access to its endpoint until patching is complete. These webhook measures are not a substitute for fixing the annotation-injection vulnerability. Re-enable admission validation after upgrading.
Patch, then assume compromise.
Upgrade ingress-nginx to version 1.11.5 or later in the 1.11 release branch, or version 1.12.1 or later in the 1.12 release branch. Audit Ingress annotations and investigate suspicious controller activity. Patching does not remediate a compromise that occurred before the upgrade.
2 exploits validated by Mallory's analysis. Hidden: 1 not yet analyzed, such as Exploit-DB entries.
15 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.