Mozilla · Firefox · CVE-2026-74973
**Name of the Vulnerable Software and Affected Versions**
Firefox versions prior to 154
Firefox ESR versions prior to 115.39
Firefox ESR versions prior to 140.14
Firefox ESR versions prior to 153.1
Thunderbird versions prior to 154
Thunderbird versions prior to 140.14
Thunderbird versions prior to 153.1
**Description**
A race condition leading to a use-after-free in the Graphics component. A race condition occurs when the timing or order of events affects the correctness of the software, and use-after-free happens when a program continues to use a pointer after it has been freed, which can lead to crashes or arbitrary code execution.
**Recommendations**
Update Firefox to version 154.
Update Firefox ESR to version 115.39.
Update Firefox ESR to version 140.14.
Update Firefox ESR to version 153.1.
Update Thunderbird to version 154.
Update Thunderbird to version 140.14.
Update Thunderbird to version 153.1.