Rancher has Privilege Escalation from Project Owner to Host
Date: 2026-07
Affected: go/github.com/rancher/rancher, go/github.com/rancher/rancher, go/github.com/rancher/rancher
Attack vector: other
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2026-41052
CWE: CWE-305
CVSS: 8.4 (CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H)

### Impact A vulnerability has been identified in Rancher Manager that allows users assigned the Project Owner role to modify Pod Security Admission (PSA) labels on namespaces within their projects. Under the default role configuration, an attacker with the following access pattern can exploit this issue: 1. **Cluster Access:** The user is granted Cluster Member access. 2. **Project Ownership:** The user creates or is assigned ownership of a project. 3. **Namespace Creation:** The user creates a namespace within that project. 4. **PSA Modification:** The user modifies the namespace PSA configuration to use the privileged profile. 5. **Privilege Escalation:** The user deploys privileged workloads within the namespace. As outlined in the [Kubernetes Pod Security Standards](https://kubernetes.io/docs/concepts/security/pod-security-standards/) documentation, `privileged` containers disable core Kubernetes security protections, allowing workloads to bypass standard container isolation boundaries. This can result in privilege escalation within the cluster environment. Potential impacts include: - Deployment of privileged containers - Access to host-level resources - Container breakout - Cluster privilege escalation - Compromise of workloads running on affected nodes Please refer to the associated MITRE ATT&CK techniques for further information about this category of attack: - [Deploy Container](https://attack.mitre.org/techniques/T1610/) - [Escape to Host](https://attack.mitre.


Mitigations:

Architectural layers (MAESTRO):