CVE-2026-6751highCWE-457CWE-824

CVE-2026-6751: high-severity vulnerability in Mozilla Firefox

Uninitialized memory in the Audio/Video: Web Codecs component

Published · Updated

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21Vexday Risk Score

No sign of exploitation. It has an official Brazilian government alert.

ssvc Trackcvss 7.3epss 0.3%
Official alert in Brazil

Brazil's federal government published an alert, recommendation or bulletin that cites this vulnerability.

  • CTIR Gov · RECOMENDAÇÃO 08/2026Recomendações de Segurança Cibernética – Atualização para a versão 150 do Mozila Firefoxread on gov.br ↗
Source: CTIR Gov (GSI) and CISC Gov.br, under the CC BY-ND 3.0 license.
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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