A Mailman security update has been released for Ubuntu Linux 20.04 LTS.

USN-5121-2: Mailman vulnerabilities

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Ubuntu Security Notice USN-5121-2
November 01, 2021

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

- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in Mailman.

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

Details:

USN-5009-1 fixed vulnerabilities in Mailman. This update provides the
corresponding updates for Ubuntu 20.04 LTS. In addition, the following CVEs
were fixed:

It was discovered that Mailman allows arbitrary content injection. An attacker
could use this to inject malicious content. (CVE-2020-12108, CVE-2020-15011)

It was discovered that Mailman improperly sanitize the MIME content. An
attacker could obtain sensitive information by sending a special type of
attachment. (CVE-2020-12137)

Original advisory details:

Andre Protas, Richard Cloke, and Andy Nuttall discovered that Mailman
did not properly associate cross-site request forgery (CSRF) tokens
to specific accounts. A remote attacker could use this to perform a
CSRF attack to gain access to another account. (CVE-2021-42097)

Andre Protas, Richard Cloke, and Andy Nuttall discovered that Mailman’s
cross-site request forgery (CSRF) tokens for the options page are
derived from the admin password. A remote attacker could possibly use
this to assist in performing a brute force attack against the admin
password. (CVE-2021-42096)

Update instructions:

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

Ubuntu 20.04 LTS:
mailman 1:2.1.29-1ubuntu3.1

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

References:
  https://ubuntu.com/security/notices/USN-5121-2
  https://ubuntu.com/security/notices/USN-5121-1
CVE-2020-12108, CVE-2020-12137, CVE-2020-15011, CVE-2021-42096,
CVE-2021-42097

Package Information:
  https://launchpad.net/ubuntu/+source/mailman/1:2.1.29-1ubuntu3.1