CVE-2026-4695: 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-2026-4695 involves incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox. This memory safety issue could lead to denial-of-service conditions (availability impact) but does not affect confidentiality or integrity. The vulnerability was resolved in Firefox 149 and Firefox ESR 140.9. The Mozilla security advisories MFSA 2026-20 and MFSA 2026-22 provide detailed information on this and other related vulnerabilities fixed in these releases. The CVSS v3.1 score is 7.5 (high), reflecting network attack vector, low attack complexity, no privileges or user interaction required, and an impact limited to availability.
Potential Impact
The vulnerability can cause denial-of-service or crash conditions in Firefox through improper handling of boundary conditions in the Web Codecs component. There is no direct impact on confidentiality or integrity. No active exploitation has been observed in the wild. The high CVSS score reflects the potential for significant disruption of service.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 149 and Firefox ESR 140.9. Users and administrators should update to these versions or later to remediate the issue. No additional mitigations are required as the vulnerability is addressed by the official patches.
CVE-2026-4695: 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-2026-4695 involves incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox. This memory safety issue could lead to denial-of-service conditions (availability impact) but does not affect confidentiality or integrity. The vulnerability was resolved in Firefox 149 and Firefox ESR 140.9. The Mozilla security advisories MFSA 2026-20 and MFSA 2026-22 provide detailed information on this and other related vulnerabilities fixed in these releases. The CVSS v3.1 score is 7.5 (high), reflecting network attack vector, low attack complexity, no privileges or user interaction required, and an impact limited to availability.
Potential Impact
The vulnerability can cause denial-of-service or crash conditions in Firefox through improper handling of boundary conditions in the Web Codecs component. There is no direct impact on confidentiality or integrity. No active exploitation has been observed in the wild. The high CVSS score reflects the potential for significant disruption of service.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 149 and Firefox ESR 140.9. Users and administrators should update to these versions or later to remediate the issue. No additional mitigations are required as the vulnerability is addressed by the official patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-03-23T23:21:52.856Z
- 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: 69c28784f4197a8e3b3205a7
Added to database: 03/24/2026, 12:45:56 UTC
Last enriched: 07/15/2026, 09:28:29 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 109
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