CVE-2026-4702 (GCVE-0-2026-4702)

Vulnerability from cvelistv5 – Published: 2026-03-24 12:30 – Updated: 2026-04-13 13:50
VLAI?
Title
JIT miscompilation in the JavaScript Engine component
Summary
JIT miscompilation in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
Severity ?
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.9 , ≤ 140.* (rpm)
Unaffected: 149 , ≤ * (rpm)
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    Mozilla Thunderbird Unaffected: 140.9 , ≤ 140.* (rpm)
Unaffected: 149 , ≤ * (rpm)
Create a notification for this product.
Credits
Evyatar Ben Asher, Keane Lucas, Nicholas Carlini, Newton Cheng, Daniel Freeman, Alex Gaynor, and Joel Weinberger using Claude from Anthropic
Show details on NVD website
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