Security Advisory
CVE-2026-84144
7.5
HIGH
Vulnerability Description
Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
Published Date
September 1, 2026
Official Source
NIST NVD Advisory