CVE-2026-5734: Vulnerability in Mozilla Firefox
CVE-2026-5734 is a set of memory safety vulnerabilities affecting Mozilla Firefox ESR 140. 9. 0, Thunderbird ESR 140. 9. 0, Firefox 149. 0. 1, and Thunderbird 149. 0. 1. These bugs showed evidence of memory corruption and could potentially be exploited to execute arbitrary code.
AI Analysis
Technical Summary
This vulnerability involves multiple memory safety bugs in Mozilla Firefox and Thunderbird versions prior to Firefox 149.0.2 and Firefox ESR 140.9.1. The bugs include memory corruption issues that could allow an attacker to execute arbitrary code with sufficient effort. Mozilla has addressed these vulnerabilities by releasing updated versions that fix the memory safety issues. The advisory references multiple related CVEs fixed simultaneously, indicating a broad effort to improve memory safety in these products. No CVSS score is provided, but the impact is assessed as high by Mozilla.
Potential Impact
The vulnerabilities could allow remote attackers to exploit memory corruption bugs to execute arbitrary code on affected systems. This could lead to full compromise of the affected Firefox or Thunderbird application processes. However, there are no reports of active exploitation in the wild. The impact is rated high by Mozilla based on the potential for arbitrary code execution.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2, and Thunderbird 149.0.2. Users and administrators should upgrade to these versions immediately to remediate the vulnerabilities. No additional mitigation steps are required beyond applying the official updates.
CVE-2026-5734: Vulnerability in Mozilla Firefox
Description
CVE-2026-5734 is a set of memory safety vulnerabilities affecting Mozilla Firefox ESR 140. 9. 0, Thunderbird ESR 140. 9. 0, Firefox 149. 0. 1, and Thunderbird 149. 0. 1. These bugs showed evidence of memory corruption and could potentially be exploited to execute arbitrary code.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves multiple memory safety bugs in Mozilla Firefox and Thunderbird versions prior to Firefox 149.0.2 and Firefox ESR 140.9.1. The bugs include memory corruption issues that could allow an attacker to execute arbitrary code with sufficient effort. Mozilla has addressed these vulnerabilities by releasing updated versions that fix the memory safety issues. The advisory references multiple related CVEs fixed simultaneously, indicating a broad effort to improve memory safety in these products. No CVSS score is provided, but the impact is assessed as high by Mozilla.
Potential Impact
The vulnerabilities could allow remote attackers to exploit memory corruption bugs to execute arbitrary code on affected systems. This could lead to full compromise of the affected Firefox or Thunderbird application processes. However, there are no reports of active exploitation in the wild. The impact is rated high by Mozilla based on the potential for arbitrary code execution.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2, and Thunderbird 149.0.2. Users and administrators should upgrade to these versions immediately to remediate the vulnerabilities. No additional mitigation steps are required beyond applying the official updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-04-07T12:43:14.328Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-25/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-27/","vendor":"Mozilla"}]
Threat ID: 69d50016aaed68159a219ce2
Added to database: 4/7/2026, 1:01:10 PM
Last enriched: 4/7/2026, 1:16:36 PM
Last updated: 4/7/2026, 2:20:43 PM
Views: 11
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