Critical Mozilla Firefox Zero-Day Allows Code Execution

Mozilla has patched a critical security vulnerability in its Firefox Web browser that's being actively exploited in the wild.

Tracked as CVE-2024-9680, the vulnerability is a use-after-free issue in Animation timelines, with attackers exploiting it to execute arbitrary code, according to Mozilla's advisory. It carries a CVSSv3 vulnerability-severity rating of 9.8 out of 10 and a low attack complexity (no privileges or user interaction is needed to successfully exploit the flaw), and translates into high risk in the event of a successful attack.

Critical bugs in Firefox, which is used by around 178 million people worldwide, are few and far between. The Web browser hasn't had to offer patches for such a severe flaw since March, and only a small number have been discovered in the past few years.

The disclosure sparked a flurry of alerts from international cyber agencies, including Dutch national cyber center Nationaal Cyber Security Centrum, and the cybersecurity centers of Canada and Italy.

The Web browser vulnerability affects Firefox 131.0.2, Firefox ESR 128.3.1, and Firefox ESR 115.16.1. Users should upgrade to version 131.0.2 in Firefox and to versions 115.16.1 or 128.3.1 for Firefox ESR to fix the vulnerability and thwart potential exploitation.