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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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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