Executive brief
Mozilla has released security updates for Firefox and Firefox ESR to address a memory safety vulnerability. This type of flaw occurs when a program incorrectly handles computer memory, which can lead to application crashes or potentially allow an attacker to execute unauthorized code. Users are advised to update their browsers to the latest versions to maintain the security of their personal data and browsing sessions.
Technical details
A memory safety vulnerability was identified in Mozilla Firefox and Firefox ESR. While specific technical details regarding the root cause (such as use-after-free or buffer overflow) are not explicitly detailed in the advisory, Mozilla classifies this as a memory safety bug that could potentially be leveraged for memory corruption. An attacker could potentially exploit this flaw by enticing a user to visit a specially crafted website. If successfully exploited, this could lead to a crash or arbitrary code execution within the context of the browser process. The issue is resolved 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: advisory
- 2026-06-16: patched