A Mailman security update has been released for Ubuntu Linux 18.04 LTS.

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Ubuntu Security Notice USN-5180-1
December 07, 2021

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

- Ubuntu 18.04 LTS

Summary:

A system hardening measure could be bypassed.

Software Description:
- mailman: Web-based mailing list manager

Details:

It was discovered that Mailman incorrectly handled CSRF tokens. A remote
list member or moderator could possibly use their own token to craft an
admin request CSRF attack and set a new admin password or make other
changes.

Update instructions:

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

Ubuntu 18.04 LTS:
mailman 1:2.1.26-1ubuntu0.6

In general, a standard system update will make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-5180-1
CVE-2021-44227

Package Information:
  https://launchpad.net/ubuntu/+source/mailman/1:2.1.26-1ubuntu0.6