CVE-2026-29773 MEDIUM

CVE-2026-29773: kubewarden-controller cross-namespace data exfiltration via deprecated host callback binding

Vendor Kubewarden
Product kubewarden-controller
Weakness CWE-863 · Incorrect authorization
Published March 9, 2026
Last update March 10, 2026

CVSS base score

4.3/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality Low
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

What the vulnerability does

01Description

Kubewarden is a policy engine for Kubernetes. Kubewarden cluster operators can grant permissions to users to deploy namespaced AdmissionPolicies and AdmissionPolicyGroups in their Namespaces. One of Kubewarden promises is that configured users can deploy namespaced policies in a safe manner, without privilege escalation. An attacker with privileged "AdmissionPolicy" create permissions (which isn't the default) could make use of 3 deprecated host-callback APIs: kubernetes/ingresses, kubernetes/namespaces, kubernetes/services. The attacker can craft a policy that exercises these deprecated API calls and would allow them read access to Ingresses, Namespaces, and Services resources respectively. This attack is read-only, there is no write capability and no access to Secrets, ConfigMaps, or other resource types beyond these three.

Key dates

02Disclosure timeline

March 9, 2026 CVE published
March 10, 2026 Record updated