CVE-2025-11721

CRITICAL

Firefox 143 and Thunderbird 143 - Memory Corruption

Title source: llm
STIX 2.1

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.

References (3)

Core 3

Scores

CVSS v3 9.8
EPSS 0.0007
EPSS Percentile 20.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact total

Details

CWE
CWE-119
Status published
Products (4)
mozilla/firefox 143.0 - 144.0
Mozilla/Firefox 144
mozilla/thunderbird 143.0 - 144.0
Mozilla/Thunderbird 144
Published Oct 14, 2025
Tracked Since Feb 18, 2026