Executive brief
Mozilla has released security updates for Firefox and Firefox ESR to address a memory safety vulnerability. Firefox is a widely used web browser for accessing internet resources. If exploited, this type of flaw could potentially allow an attacker to cause the browser to crash or execute unauthorized code, which could lead to the theft of sensitive user data or unauthorized access to the user's system.
Technical details
A memory safety vulnerability was identified in Mozilla Firefox and Firefox ESR. While specific technical details regarding the root cause (e.g., buffer overflow, use-after-free) are not disclosed in the advisory, the flaw is categorized as a memory safety bug that could lead to memory corruption. An attacker could potentially exploit this by enticing a user to visit a specially crafted website. Successful exploitation could allow for arbitrary code execution within the context of the browser process. The vulnerability is addressed in Firefox 152 and Firefox ESR 140.12.
Affected products
- Mozilla Firefox < 152
- Mozilla Firefox ESR < 140.12
Timeline
- 2026-06-16: disclosed
- 2026-06-16: patched