cbcvebase.
CVE-2026-84119
published 2026-09-01

CVE-2026-84119: Sandbox escape due to use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15…

PriorityP348critical9.6CVSS 3.1
AVNACLPRNUIRSCCHIHAH
Sandbox escape due to use-after-free in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.

Affected

14 ranges
VendorProductVersion rangeFixed in
mozillafirefox< Firefox 155Firefox 155
mozillafirefox< 115.40.0115.40.0
mozillafirefox>= 116.0 < 140.15.0140.15.0
mozillafirefox>= 141.0.0 < 153.2.0153.2.0
mozillafirefox>= 154.0.0 < 155.0.0155.0.0
mozillafirefox_esr< Firefox ESR 153.2Firefox ESR 153.2
mozillafirefox_esr< Firefox ESR 140.15Firefox ESR 140.15
mozillafirefox_esr< Firefox ESR 115.40Firefox ESR 115.40
mozillathunderbird< Thunderbird 140.15Thunderbird 140.15
mozillathunderbird< Thunderbird 153.2Thunderbird 153.2
mozillathunderbird< Thunderbird 155Thunderbird 155
mozillathunderbird< 140.15.0140.15.0
mozillathunderbird>= 141.0 < 153.2.0153.2.0
mozillathunderbird>= 154.0 < 155.0155.0
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