CVE-2026-4701 (GCVE-0-2026-4701)

Vulnerability from cvelistv5 – Published: 2026-03-24 12:30 – Updated: 2026-04-13 13:50
VLAI?
Title
Use-after-free in the JavaScript Engine component
Summary
Use-after-free 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
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
Gary Kwong
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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