VULNERABILITY INTELLIGENCE

CVE-2025-6436

CVSS score8.1 HIGH
EPSS probability4.26%
CISA KEVNot currently listed
Published2025-06-24
Last modified2026-09-30
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

Memory safety bugs present in Firefox 139 and Thunderbird 139. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 140 and Thunderbird 140.

Weakness classification

  • CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

Primary references