CVE-2026-2793 — Out-of-bounds Write in Mozilla Firefox
Severity
9.8CRITICALNVD
EPSS
0.1%
top 78.32%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedFeb 24
Description
Memory safety bugs present in Firefox ESR 115.32, Firefox ESR 140.7, Thunderbird ESR 140.7, Firefox 147 and Thunderbird 147. 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 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitability: 3.9 | Impact: 5.9
Affected Packages3 packages
🔴Vulnerability Details
3📋Vendor Advisories
7🕵️Threat Intelligence
1💬Community
1Bugzilla▶
CVE-2026-2793 firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148↗2026-02-24