A Mutt vulnerability and regression has been released for Ubuntu Linux 20.04 LTS, 19.10, 18.04 LTS, 16.04 LTS, and 12.04 ESM.

USN-4403-1: Mutt vulnerability and regression

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Ubuntu Security Notice USN-4403-1
June 24, 2020

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

- Ubuntu 20.04 LTS
- Ubuntu 19.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 12.04 ESM

Summary:

Mutt could be made to enable MITM attacks if it received a specially crafted
request.

Software Description:
- mutt: text-based mailreader supporting MIME, GPG, PGP and threading

Details:

It was discovered that Mutt incorrectly handled certain requests.
An attacker could possibly use this issue to enable MITM attacks.
(CVE-2020-14954)

This update also address a regression caused in the last update USN-4401-1.
It only affected Ubuntu 12.04 ESM, Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 19.10.

Update instructions:

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

Ubuntu 20.04 LTS:
mutt 1.13.2-1ubuntu0.2

Ubuntu 19.10:
mutt 1.10.1-2.1ubuntu0.2

Ubuntu 18.04 LTS:
mutt 1.9.4-3ubuntu0.3

Ubuntu 16.04 LTS:
mutt 1.5.24-1ubuntu0.4

Ubuntu 12.04 ESM:
mutt 1.5.21-5ubuntu2.5

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

References:
  https://usn.ubuntu.com/4403-1
CVE-2020-14954,   https://launchpad.net/bugs/1884588

Package Information:
  https://launchpad.net/ubuntu/+source/mutt/1.13.2-1ubuntu0.2
  https://launchpad.net/ubuntu/+source/mutt/1.10.1-2.1ubuntu0.2
  https://launchpad.net/ubuntu/+source/mutt/1.9.4-3ubuntu0.3
  https://launchpad.net/ubuntu/+source/mutt/1.5.24-1ubuntu0.4