CVE-2026-4697: Vulnerability in Mozilla Firefox
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
AI Analysis
Technical Summary
CVE-2026-4697 is a memory safety vulnerability caused by incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox. It affects Firefox versions before 149 and was addressed by Mozilla in Firefox 149 and Firefox ESR 140.9. The vulnerability is part of a broader set of memory safety bugs fixed in these releases. The CVSS 3.1 base score is 7.5 (high), with attack vector network, low attack complexity, no privileges required, no user interaction, and impact limited to availability (denial-of-service). The vendor advisory confirms the fix and recommends updating to the patched versions.
Potential Impact
The vulnerability can cause denial-of-service conditions due to memory safety issues in the Web Codecs component. While no direct evidence of code execution is provided, memory corruption could potentially be leveraged for more severe impacts with sufficient effort. No known active exploitation has been reported.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 149 and Firefox ESR 140.9. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official update.
CVE-2026-4697: Vulnerability in Mozilla Firefox
Description
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-4697 is a memory safety vulnerability caused by incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox. It affects Firefox versions before 149 and was addressed by Mozilla in Firefox 149 and Firefox ESR 140.9. The vulnerability is part of a broader set of memory safety bugs fixed in these releases. The CVSS 3.1 base score is 7.5 (high), with attack vector network, low attack complexity, no privileges required, no user interaction, and impact limited to availability (denial-of-service). The vendor advisory confirms the fix and recommends updating to the patched versions.
Potential Impact
The vulnerability can cause denial-of-service conditions due to memory safety issues in the Web Codecs component. While no direct evidence of code execution is provided, memory corruption could potentially be leveraged for more severe impacts with sufficient effort. No known active exploitation has been reported.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 149 and Firefox ESR 140.9. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-03-23T23:21:57.119Z
- Cvss Version
- null
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-20/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-22/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-23/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-24/","vendor":"Mozilla"}]
Threat ID: 69c28784f4197a8e3b3205b2
Added to database: 03/24/2026, 12:45:56 UTC
Last enriched: 07/15/2026, 09:28:36 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 111
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