Mozilla Firefox and Thunderbird Use-After-Free Vulnerability in Line Breaking

A use-after-free vulnerability has been identified in Mozilla Firefox and Thunderbird. This issue arises when lines of text are broken, assuming a controlled failed memory allocation, which can lead to a potentially exploitable crash. The vulnerability is present in Firefox versions prior to 134, Firefox ESR versions prior to 128.6 and 115.19, as well as Thunderbird versions prior to 134 and 128.6.

Impact

Exploitation of this vulnerability can lead to a use-after-free condition, causing a memory corruption issue that could be exploited to execute arbitrary code.

Remediation

Users can upgrade to Firefox 134, Thunderbird 134, Firefox ESR 128.6, or Thunderbird ESR 128.6 to address this vulnerability.