CVE-2025-11721: Memory safety bug fixed in Firefox 144 and Thunderbird 144
Published Oct 14, 2025
·Updated
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.
Affected Software
4 affected componentsFixes available
Mozilla Firefox<144
144
Mozilla Thunderbird<144
144
Mozilla Firefox>=143.0<144.0
Mozilla Thunderbird>=143.0<144.0
Event History
Oct 14, 2025
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·12:27 PM
Data Sourced
via MITRE·12:27 PM
Description
Data Sourced
via NVD·01:15 PM
DescriptionSeverityWeaknessAffected Software
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
1
What is the severity of CVE-2025-11721?
CVE-2025-11721 is a memory safety vulnerability that could potentially allow for arbitrary code execution.
2
How do I fix CVE-2025-11721?
To mitigate CVE-2025-11721, users should upgrade to Firefox or Thunderbird version 144 or later.
3
Which software is affected by CVE-2025-11721?
CVE-2025-11721 affects Mozilla Firefox and Thunderbird versions prior to 144.
4
What type of vulnerability is CVE-2025-11721?
CVE-2025-11721 is classified as a memory safety bug.
5
Is there any evidence of exploitation for CVE-2025-11721?
CVE-2025-11721 shows evidence of memory corruption, suggesting a potential pathway for exploitation.