CVE-2025-6436 (GCVE-0-2025-6436)

Vulnerability from cvelistv5 – Published: 2025-06-24 12:28 – Updated: 2026-04-13 14:31
VLAI?
Title
Memory safety bugs fixed in Firefox 140 and Thunderbird 140
Summary
Memory safety bugs present in Firefox 139 and Thunderbird 139. 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 was fixed in Firefox 140 and Thunderbird 140.
Severity ?
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140 , ≤ * (rpm)
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Mozilla Thunderbird Unaffected: 140 , ≤ * (rpm)
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Credits
Andrew McCreight, Gabriele Svelto, Beth Rennie (she/her), Steven Michaud, the Mozilla Fuzzing Team
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Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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.



Detection rules are retrieved from Rulezet.