A flaw introduced in CRI-O version 1.19 which an attacker can use to bypass the safeguards and set arbitrary kernel parameters on the host. As a result, anyone with rights to deploy a pod on a Kubernetes cluster that uses the CRI-O runtime can abuse the kernel.core_pattern
kernel parameter to achieve container escape and arbitrary code execution as root on any node in the cluster.
The patches will be present in 1.19.6, 1.20.7, 1.21.6, 1.22.3, 1.23.2, 1.24.0
+
in the sysctl value of a pod.apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: sysctl-psp
spec:
forbiddenSysctls:
- "*"
However, this option will not work if any sysctls are required by any pods in the cluster.Credit for finding this vulnerability goes to John Walker and Manoj Ahuje of Crowdstrike. The CRI-O community deeply thanks them for the report.
If you have any questions or comments about this advisory: * Open an issue in the CRI-O repo * To make a report, email your vulnerability to the private cncf-crio-security@lists.cncf.io list with the security details and the details expected for all CRI-O bug reports.
{ "nvd_published_at": "2022-03-16T15:15:00Z", "cwe_ids": [ "CWE-94" ], "severity": "HIGH", "github_reviewed": true, "github_reviewed_at": "2022-03-15T20:13:38Z" }