CVE-2026-8946: Vulnerability in Mozilla Firefox
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI Analysis
Technical Summary
CVE-2026-8946 involves incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox, classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). This vulnerability was addressed and fixed in Firefox 151 and Firefox ESR 115.36. The CVSS v3.1 base score is 7.5, indicating a high impact with network attack vector, low attack complexity, no privileges required, no user interaction, and high confidentiality impact but no integrity or availability impact. The vendor advisory confirms the fix in Firefox 151 and ESR 115.36. No known exploits have been reported.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption, potentially allowing an attacker to access sensitive information (confidentiality impact). The vulnerability does not impact integrity or availability. There are no reports of active exploitation in the wild.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update affected Firefox versions to Firefox 151 or later, or Firefox ESR 115.36 or later. No additional mitigation actions are indicated by the vendor advisory.
CVE-2026-8946: Vulnerability in Mozilla Firefox
Description
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-8946 involves incorrect boundary conditions in the Audio/Video: Web Codecs component of Mozilla Firefox, classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). This vulnerability was addressed and fixed in Firefox 151 and Firefox ESR 115.36. The CVSS v3.1 base score is 7.5, indicating a high impact with network attack vector, low attack complexity, no privileges required, no user interaction, and high confidentiality impact but no integrity or availability impact. The vendor advisory confirms the fix in Firefox 151 and ESR 115.36. No known exploits have been reported.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption, potentially allowing an attacker to access sensitive information (confidentiality impact). The vulnerability does not impact integrity or availability. There are no reports of active exploitation in the wild.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update affected Firefox versions to Firefox 151 or later, or Firefox ESR 115.36 or later. No additional mitigation actions are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:29:35.532Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-47/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-48/","vendor":"Mozilla"}]
Threat ID: 6a0c6779ec166c07b0a99379
Added to database: 05/19/2026, 13:36:57 UTC
Last enriched: 07/15/2026, 08:14:43 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 86
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