cbcvebase.
CVE-2025-11721
published 2025-10-14

CVE-2025-11721: 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…

PriorityP348critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.34%
26.2th percentile
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

4 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 144.0-1 (sid)firefox 144.0-1 (sid)
mozillafirefox
mozillafirefox>= 143.0 < 144.0144.0
mozillathunderbird>= 143.0 < 144.0144.0

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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