A containerd security update has been released for Ubuntu Linux 16.04 LTS, 18.04 LTS, 20.04 LTS, and 20.10.

USN-4653-1: containerd vulnerability

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Ubuntu Security Notice USN-4653-1
November 30, 2020

containerd vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

containerd could be made to crash or run programs as an administrator
if it opened a specially crafted file.

Software Description:
- containerd: daemon to control runC

Details:

It was discovered that access controls for the shim’s API socket did not
restrict access to the abstract unix domain socket in some cases. An attacker
could use this vulnerability to run containers with elevated privileges.

Update instructions:

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

Ubuntu 20.10:
containerd 1.3.7-0ubuntu3.1

Ubuntu 20.04 LTS:
containerd 1.3.3-0ubuntu2.1

Ubuntu 18.04 LTS:
containerd 1.3.3-0ubuntu1~18.04.3

Ubuntu 16.04 LTS:
containerd 1.2.6-0ubuntu1~16.04.5

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

References:
  https://usn.ubuntu.com/4653-1
CVE-2020-15257

Package Information:
  https://launchpad.net/ubuntu/+source/containerd/1.3.7-0ubuntu3.1
  https://launchpad.net/ubuntu/+source/containerd/1.3.3-0ubuntu2.1
  https://launchpad.net/ubuntu/+source/containerd/1.3.3-0ubuntu1~18.04.3
  https://launchpad.net/ubuntu/+source/containerd/1.2.6-0ubuntu1~16.04.5