Memory safety bugs present in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. 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 affects Firefox < 149 and Firefox ESR < 140.9.
CVE-2026-4720
NONE
Updated Mar 24, 2026
Firefox
CVE Details
CVE ID
CVE-2026-4720
Published Date
Mar 24, 2026
Vendor
Firefox
Severity
NONE
Impact
Minimal impact
Source
View Advisory