Critical Use-After-Free Vulnerability in Mozilla Firefox and Thunderbird

What changed

A critical use-after-free vulnerability has been identified in Mozilla Firefox and Thunderbird, specifically affecting the handling of animation timelines. This flaw allows attackers to execute arbitrary code within the content process, posing a significant risk to users.

Reports indicate that this vulnerability is being actively exploited in the wild, necessitating immediate attention from users and administrators.

Who is affected

The following products and versions are impacted by this vulnerability:

Mozilla Firefox versions prior to 131.0.2, Firefox ESR versions before 128.3.1 and 115.16.1, as well as Thunderbird versions below 131.0.1, 128.3.1, and 115.16.0.

• Mozilla Firefox (versions < 131.0.2)
• Mozilla Firefox ESR (versions < 128.3.1 and < 115.16.1)
• Mozilla Thunderbird (versions < 131.0.1, < 128.3.1, and < 115.16.0)

What to do

Users and administrators should prioritize updating their Mozilla Firefox and Thunderbird installations to the latest versions to mitigate the risk associated with this vulnerability.

Regularly monitoring security advisories and applying patches promptly is essential to maintain a secure environment.

• Update Mozilla Firefox to version 131.0.2 or later.
• Update Mozilla Thunderbird to version 131.0.1 or later.
• Implement security best practices to minimize exposure to potential exploits.