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Appaloosa Scout

Vulnerability · NVD

CVE-2026-4689

CRITICAL 10.0

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Attack vector : Network No privileges required No user interaction
Show raw CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS 0.66% exploit very unlikely percentile 48.4%

Tracked apps referencing this CVE

For each app: the affected range, the fixing version, and where the tracked app stands today.

Vulnerable CPE configurations (2)
Vendor Product Versions
mozilla thunderbird
All platforms (wildcard)
<140.9.0
mozilla thunderbird
All platforms (wildcard)
<149.0
View on NVD ↗ Advisory · www.mozilla.org