cbcvebase.
CVE-2026-84144
published 2026-09-01

CVE-2026-84144: Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another…

PriorityP341high7.5CVSS 3.1
AVNACHPRNUIRSUCHIHAH
EPSS
0.24%
15.4th percentile
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.

Affected

8 ranges
VendorProductVersion rangeFixed in
mozillafirefox< Firefox 155Firefox 155
mozillafirefox< 153.2.0153.2.0
mozillafirefox>= 154.0.0 < 155.0.0155.0.0
mozillafirefox_esr< Firefox ESR 153.2Firefox ESR 153.2
mozillathunderbird< Thunderbird 155Thunderbird 155
mozillathunderbird< Thunderbird 153.2Thunderbird 153.2
mozillathunderbird< 153.2.0153.2.0
mozillathunderbird>= 154.0 < 155.0155.0
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