CVE-2026-84143
CVE CVE-2026-84143EUVD EUVD-2026-69091Published 2026-09-01T12:19:10.000ZLast changed 2026-09-03T17:23:35.000ZCVSS 9.8
What the advisory describes
Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. 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 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Source: EUVD (ENISA), in the words of the advisory.
Products the advisory names
These come from the advisory itself, not from any check we performed.
- Mozilla — Firefox 140.15; 153.2; 155
- Mozilla — Thunderbird 140.15; 153.2; 155
The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.
Carried in the product catalogue
An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.
- Mozilla — Firefox
- Mozilla — Thunderbird
Does this concern one of your customers?
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