A SquirrelMail security update has been released for Ubuntu Linux 16.04 LTS.

USN-4669-1: SquirrelMail vulnerability

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Ubuntu Security Notice USN-4669-1
December 10, 2020

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

- Ubuntu 16.04 LTS

Summary:

SquirrelMail could be made to crash if it received specially crafted
input.

Software Description:
- squirrelmail: Webmail for nuts

Details:

It was discovered that a cross-site scripting (XSS) vulnerability in
SquirrelMail allows remote attackers to use malicious script content from
HTML e-mail to execute code and/or provoke a denial of service.

Update instructions:

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

Ubuntu 16.04 LTS:
squirrelmail 2:1.4.23~svn20120406-2+deb8u3ubuntu0.16.04.2

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

References:
  https://usn.ubuntu.com/4669-1
CVE-2019-12970

Package Information:
  https://launchpad.net/ubuntu/+source/squirrelmail/2:1.4.23~svn20120406-2+deb8u3ubuntu0.16.04.2