CVE-2026-6763 (GCVE-0-2026-6763)

Vulnerability from cvelistv5 – Published: 2026-04-21 12:40 – Updated: 2026-04-21 23:34
VLAI?
Title
Mitigation bypass in the File Handling component
Summary
Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Severity ?
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-693 - Protection Mechanism Failure
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.10 , ≤ 140.* (rpm)
Unaffected: 150 , ≤ * (rpm)
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    Mozilla Thunderbird Unaffected: 140.10 , ≤ 140.* (rpm)
Unaffected: 150 , ≤ * (rpm)
Create a notification for this product.
Credits
Tomoya Nakanishi
Show details on NVD website
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Sightings

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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.



Detection rules are retrieved from Rulezet.