CVE-2026-4729 (GCVE-0-2026-4729)

Vulnerability from cvelistv5 – Published: 2026-03-24 12:30 – Updated: 2026-03-25 13:08
VLAI?
Title
Memory safety bugs fixed in Firefox 149 and Thunderbird 149
Summary
Memory safety bugs present in Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149 and Thunderbird < 149.
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-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Affected: unspecified , < 149 (custom)
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    Mozilla Thunderbird Affected: unspecified , < 149 (custom)
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Credits
Christian Holler, Fatih Kilic, Tom Schuster and the Mozilla Fuzzing Team
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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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