It was discovered that libvirt incorrectly handled an active pool without a target path. A remote attacker could possibly use this issue to cause libvirt to crash, resulting in a denial of service. (CVE-2020-10703) It was discovered that libvirt incorrectly handled memory when retrieving certain domain statistics. A remote attacker could possibly use this issue to cause libvirt to consume resources, resulting in a denial of service. This issue only affected Ubuntu 19.10. (CVE-2020-12430)

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.

A large number of security issues were discovered in the WebKitGTK+ Web and JavaScript engines. If a user were tricked into viewing a malicious website, a remote attacker could exploit a variety of issues related to web browser security, including cross-site scripting attacks, denial of service attacks, and arbitrary code execution.