CVE-2026-4716: Vulnerability in Mozilla Firefox
Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
AI Analysis
Technical Summary
CVE-2026-4716 describes a memory safety vulnerability in the JavaScript Engine component of Mozilla Firefox caused by incorrect boundary conditions and uninitialized memory usage. This vulnerability is part of a broader set of memory safety bugs fixed in Firefox 149 and Firefox ESR 140.9. The CVSS v3.1 score is 9.1 (critical), indicating network attack vector, no privileges required, no user interaction, and high impact on confidentiality and availability. The vendor advisory confirms the issue was resolved in the stated Firefox versions, with no known active exploitation.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption, potentially allowing an attacker to execute arbitrary code remotely or cause denial of service. The CVSS score of 9.1 reflects critical severity with high confidentiality and availability impact. However, no known exploits in the wild have been reported as of the advisory date.
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. Since this is not a cloud service, patching the client software is required. There are no vendor advisories indicating that no action is required or that the issue is already mitigated without patching.
CVE-2026-4716: Vulnerability in Mozilla Firefox
Description
Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS v3.1
Score 9.1critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-4716 describes a memory safety vulnerability in the JavaScript Engine component of Mozilla Firefox caused by incorrect boundary conditions and uninitialized memory usage. This vulnerability is part of a broader set of memory safety bugs fixed in Firefox 149 and Firefox ESR 140.9. The CVSS v3.1 score is 9.1 (critical), indicating network attack vector, no privileges required, no user interaction, and high impact on confidentiality and availability. The vendor advisory confirms the issue was resolved in the stated Firefox versions, with no known active exploitation.
Potential Impact
Successful exploitation of this vulnerability could lead to memory corruption, potentially allowing an attacker to execute arbitrary code remotely or cause denial of service. The CVSS score of 9.1 reflects critical severity with high confidentiality and availability impact. However, no known exploits in the wild have been reported as of the advisory date.
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. Since this is not a cloud service, patching the client software is required. There are no vendor advisories indicating that no action is required or that the issue is already mitigated without patching.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-03-23T23:22:33.703Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 69c28788f4197a8e3b3206e7
Added to database: 03/24/2026, 12:46:00 UTC
Last enriched: 04/14/2026, 12:13:03 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 86
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