Kata Containers have VM Escape via virtiofsd Argument Injection through Default-Enabled Pod Annotations

Summary

Kata Containers is an open source project focusing on a standard implementation of lightweight Virtual Machines (VMs) that perform like containers. Versions prior to 3.31.0 ship with a default configuration that allows pod creators to inject arbitrary command-line arguments into the virtiofsd process through the `io.katacontainers.config.hypervisor.virtio_fs_extra_args` pod annotation. By injecting `-o source=/` along with `--no-announce-submounts` and `--sandbox=none`, an attacker can override the virtiofsd shared directory to serve the entire host root filesystem into the guest VM. Combined with the `kernel_params` annotation (also enabled by default) to activate the agent debug console, the attacker can mount the host filesystem from inside the VM and read or write any file on the host, including /etc/shadow. Version 3.31.0 patches the issue.

Timeline

1. Jul 23, 2026, 5:32 PM UTCCVE published
2. Jul 24, 2026, 10:02 PM UTCCISA SSVC assessment

   Exploitation: poc · Automatable: yes · Technical impact: total

3. Jul 24, 2026, 10:03 PM UTCRecord last updated

Affected versions

• kata-containers kata-containers

  fixed in 3.31.0

• github.com/kata-containers/kata-containersGo

  fixed in 0.0.0-20260519062212-ffa59ce3aa78

References 2