CVE-2026-8974: Vulnerability in Mozilla Firefox
Memory safety bugs present in Firefox ESR 140.10 and Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI Analysis
Technical Summary
This vulnerability involves multiple memory safety bugs in Firefox ESR 140.10 and Firefox 150, some of which demonstrated memory corruption that could allow arbitrary code execution with sufficient effort. The issues are categorized under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). Mozilla addressed these vulnerabilities by releasing patches in Firefox 151 and Firefox ESR 140.11. The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. The vendor advisories (MFSA 2026-46 and MFSA 2026-48) provide detailed information and confirm the remediation status.
Potential Impact
Successful exploitation of these memory safety bugs could lead to arbitrary code execution, compromising the confidentiality, integrity, and availability of the affected systems. The vulnerabilities affect Firefox ESR 140.10 and Firefox 150, which are widely used versions. No active exploitation has been observed in the wild as per current data.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 151 and Firefox ESR 140.11. Users and administrators should upgrade to these or later versions to remediate the issue. Since patches are available and the vendor advisory confirms the fix, no additional mitigation steps are required beyond applying the updates.
CVE-2026-8974: Vulnerability in Mozilla Firefox
Description
Memory safety bugs present in Firefox ESR 140.10 and Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
CVSS v3.1
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves multiple memory safety bugs in Firefox ESR 140.10 and Firefox 150, some of which demonstrated memory corruption that could allow arbitrary code execution with sufficient effort. The issues are categorized under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). Mozilla addressed these vulnerabilities by releasing patches in Firefox 151 and Firefox ESR 140.11. The CVSS v3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. The vendor advisories (MFSA 2026-46 and MFSA 2026-48) provide detailed information and confirm the remediation status.
Potential Impact
Successful exploitation of these memory safety bugs could lead to arbitrary code execution, compromising the confidentiality, integrity, and availability of the affected systems. The vulnerabilities affect Firefox ESR 140.10 and Firefox 150, which are widely used versions. No active exploitation has been observed in the wild as per current data.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 151 and Firefox ESR 140.11. Users and administrators should upgrade to these or later versions to remediate the issue. Since patches are available and the vendor advisory confirms the fix, no additional mitigation steps are required beyond applying the updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:30:22.393Z
- 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/mfsa2026-48/","vendor":"Mozilla"}]
Threat ID: 6a0c6782ec166c07b0a99bc6
Added to database: 05/19/2026, 13:37:06 UTC
Last enriched: 05/26/2026, 20:11:23 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 86
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