Critical severity9.8NVD Advisory· Published Oct 14, 2025· Updated Apr 13, 2026

CVE-2025-11721

Description

Memory safety bug present in Firefox 143 and Thunderbird 143. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 144 and Thunderbird 144.

Affected products

Mozilla Corporation/Firefox
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
Range: >=143.0,<144.0
Mozilla Corporation/Thunderbird
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
Range: >=143.0,<144.0

Patches

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

www.mozilla.org/security/advisories/mfsa2025-81/nvdVendor Advisory
www.mozilla.org/security/advisories/mfsa2025-84/nvdVendor Advisory
bugzilla.mozilla.org/show_bug.cginvdIssue TrackingPermissions Required

News mentions

No linked articles in our index yet.

cvss	0.637
epss	0.000
exploit	0.000
kev	0.000
patch	0.000
ransomware	0.000