CVE-2026-53488 is a vulnerability in containerd's CRI plugin where labels from an image configuration (LABEL instruction in Dockerfile) are propagated to containers without validation. This allows an attacker who can cause a crafted container image to be pulled and run to execute arbitrary commands on the host system through plugins that consume container labels, such as the restart-monitor binary:// logger. The primary impact is host-root command execution, enabling unauthorized control over the host. The vulnerability is addressed by Helm version 3.21.1-r1 and updates to Red Hat's multicluster engine for Kubernetes. Mitigations include restricting image pulls to trusted registries and disabling or restricting the binary:// logger URI scheme in containerd.

The vulnerability allows an attacker with the ability to cause a crafted container image to be pulled and run to execute arbitrary commands on the host system with root privileges. This can lead to full compromise of the host, including unauthorized code execution, data modification, and denial of service. The severity is rated high with a CVSS v3 base score of 8.8 by Red Hat, reflecting high confidentiality, integrity, and availability impacts.

A fix is available in Helm version 3.21.1-r1 and corresponding Red Hat multicluster engine for Kubernetes releases. Users should upgrade to these fixed versions. Additionally, restrict container image pulls to trusted registries using admission policies or image signature verification. Where containerd is used as the container runtime, disable or restrict the binary:// logger URI scheme in the containerd configuration to prevent exploitation via unvalidated labels. Follow vendor documentation for detailed installation and configuration guidance.