Firefox 147 Security Update Fixes Sandbox Escapes and Memory-Safety Bugs

Mozilla released Firefox 147 with fixes for 16 security vulnerabilities, including multiple high-severity sandbox escape issues and memory-safety flaws that could enable arbitrary code execution if exploited. Reported problem areas include the Graphics stack (notably WebGL/Canvas-related code paths), the Messaging System, IPC, and other core browser components; the fixes also apply to Firefox ESR 140.7 and Thunderbird ESR 140.7/147, with vendors urging users to update promptly given ongoing browser-targeted attack activity.

Public reporting highlights that several of the most serious issues involve bypassing Firefox’s isolation model via sandbox escapes in graphics and messaging components, alongside memory corruption bugs (including issues described as likely exploitable with sufficient effort). While no confirmed in-the-wild exploitation was reported in the coverage, the concentration of high-impact graphics-related vulnerabilities underscores continued risk in complex rendering surfaces such as WebGL and Canvas, reinforcing the need for rapid patch deployment across managed endpoints.