CVE WatchJul 15, 2026

CVE-2026-4689

Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability was fixed in Firefox 149, F

CVSS

10.0

Critical

EPSS

0.7%

p48

KEV

—

Exploit Today

0-100

Published: Mar 24, 2026 · Last modified: Jul 15, 2026 · CWE-190 · CWE-754 · CWE-120

EPSS · 30d

0.7%EPSS · 30 days0.7%

2026-06-302026-07-17

Technical description

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.

Official references

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