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

USN-4505-1: PHPMailer vulnerability

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Ubuntu Security Notice USN-4505-1
September 16, 2020

libphp-phpmailer vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS

Summary:

Attachments with specially crafted filenames could bypass filename-based
mail attachment filters.

Software Description:
- libphp-phpmailer: full featured email transfer class for PHP

Details:

Elar Lang discovered that PHPMailer did not properly escape double quote
characters in filenames. A remote attacker could possibly exploit this
with a crafted filename to bypass attachment filters that are based on
matching filename extensions. (CVE-2020-13625)

Update instructions:

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

Ubuntu 18.04 LTS:
libphp-phpmailer 5.2.14+dfsg-2.3+deb9u2build0.18.04.1

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

References:
  https://usn.ubuntu.com/4505-1
CVE-2020-13625

Package Information:
  https://launchpad.net/ubuntu/+source/libphp-phpmailer/5.2.14+dfsg-2.3+deb9u2build0.18.04.1