Containerd is a daemon with an API and a command line client, to manage containers on one machine. It uses runC to run containers according to the OCI specification.
Multiple vulnerabilities have been discovered in containerd. Please review the CVE identifiers referenced below for details.
A local attacker, able to run a malicious container in the same network namespace as the shim, could possibly escalate privileges. Furthermore, an attacker could disclose sensitive information.
There is no known workaround at this time.
All containerd users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=app-emulation/containerd-1.4.4"