CVE-2026-74987

Summary

Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. 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 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

Affected Software

VendorProductVersion RangeStatus
MozillaFirefox140.14 <= 140.*unaffected
MozillaFirefox153.1 <= 153.*unaffected
MozillaFirefox154 <= *unaffected
MozillaThunderbird140.14 <= 140.*unaffected
MozillaThunderbird153.1 <= 153.*unaffected
MozillaThunderbird154 <= *unaffected

Weaknesses

References