CVE-2026-6751: Vulnerability in Mozilla Firefox
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.
AI Analysis
Technical Summary
CVE-2026-6751 is a memory safety vulnerability caused by uninitialized memory usage within the Audio/Video: Web Codecs component of Mozilla Firefox. This flaw could potentially lead to memory corruption. Mozilla fixed this vulnerability in Firefox 150 and Firefox ESR 140.10 as part of a security update addressing multiple memory safety bugs. The vendor advisories confirm the fix and classify the impact as high. No CVSS score is provided, but the impact is considered high based on vendor assessment.
Potential Impact
The vulnerability involves uninitialized memory, which can lead to memory corruption and potentially exploitable conditions. Mozilla classifies the impact as high. There are no known exploits in the wild at this time. The issue affects Firefox versions prior to 150 and Firefox ESR versions prior to 140.10. Successful exploitation could compromise the security of affected Firefox installations.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the issue. Since this is a client software vulnerability, patching the affected Firefox installations is the primary and recommended mitigation. No additional mitigations are specified or required beyond applying the official update.
CVE-2026-6751: Vulnerability in Mozilla Firefox
Description
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-6751 is a memory safety vulnerability caused by uninitialized memory usage within the Audio/Video: Web Codecs component of Mozilla Firefox. This flaw could potentially lead to memory corruption. Mozilla fixed this vulnerability in Firefox 150 and Firefox ESR 140.10 as part of a security update addressing multiple memory safety bugs. The vendor advisories confirm the fix and classify the impact as high. No CVSS score is provided, but the impact is considered high based on vendor assessment.
Potential Impact
The vulnerability involves uninitialized memory, which can lead to memory corruption and potentially exploitable conditions. Mozilla classifies the impact as high. There are no known exploits in the wild at this time. The issue affects Firefox versions prior to 150 and Firefox ESR versions prior to 140.10. Successful exploitation could compromise the security of affected Firefox installations.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 150 and Firefox ESR 140.10. Users and administrators should update to these versions or later to remediate the issue. Since this is a client software vulnerability, patching the affected Firefox installations is the primary and recommended mitigation. No additional mitigations are specified or required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-04-21T12:40:47.871Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-30/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-32/","vendor":"Mozilla"}]
Threat ID: 69e7789819fe3cd2cdd1625d
Added to database: 4/21/2026, 1:16:08 PM
Last enriched: 4/21/2026, 1:47:09 PM
Last updated: 4/22/2026, 7:26:08 AM
Views: 9
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