Ubuntu 21.04 USN-5012-1 Critical: containerd File Permissions Issue

ubuntu

July 20, 2021

containerd could be made to overwrite file permissions.

Summary

containerd could be made to overwrite file permissions.

Software Description:

- containerd: daemon to control runC

Details:

It was discovered that containerd incorrectly handled file permission

changes. If a user or automated system were tricked into launching a

specially crafted container image, a remote attacker could change

permissions on files on the host filesystem and possibly escalate

privileges.

Topics Covered

security advisory privilege escalation Ubuntu permissions issue containerd

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 21.04:
  containerd                      1.5.2-0ubuntu1~21.04.2

Ubuntu 20.10:
  containerd                      1.5.2-0ubuntu1~20.10.2

Ubuntu 20.04 LTS:
  containerd                      1.5.2-0ubuntu1~20.04.2

Ubuntu 18.04 LTS:
  containerd                      1.5.2-0ubuntu1~18.04.2

After a standard system update you need to restart containerd to make
all the necessary changes.