CVE-2026-4690
Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component
CVSS Score
9.6
EPSS Score
0.0%
EPSS Percentile
0th
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.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Mar 24, 2026 |
| Last Updated | Apr 13, 2026 |
Stay Ahead of the Next One
Get instant alerts for mozilla firefox
Be the first to know when new critical vulnerabilities affecting mozilla firefox are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2016375 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-20/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-21/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-22/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-23/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-24/
Credits
Sajeeb Lohani