CVE-2026-6751 (GCVE-0-2026-6751)

Vulnerability from cvelistv5 – Published: 2026-04-21 12:40 – Updated: 2026-04-21 23:34
VLAI?
Title
Uninitialized memory in the Audio/Video: Web Codecs component
Summary
Uninitialized memory in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Severity ?
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CWE
  • CWE-457 - Use of Uninitialized Variable
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
Joren Afman
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.



Detection rules are retrieved from Rulezet.