CVE-2026-6784

CVE-2026-6784 is a memory safety vulnerability affecting Firefox 149 and Thunderbird 149, with evidence of potential memory corruption that could enable arbitrary code execution if exploited. The flaw was addressed in the subsequent releases of both applications (Firefox 150 and Thunderbird 150). Memory safety bugs of this nature in major browser and email client software represent significant security concerns due to their widespread user base. The vulnerability carries a CVSS score of 7.5 (HIGH), indicating substantial risk across multiple impact categories. The attack requires network access but involves high complexity and user interaction to exploit. Successful exploitation could result in high-severity consequences, including confidentiality breaches, integrity violations, and availability compromise. The EPSS score of 0.000390000 indicates this vulnerability ranks higher than most disclosed CVEs in terms of exploitability likelihood. While CVE-2026-6784 is not currently listed on CISA's Known Exploited Vulnerabilities (KEV) catalog, it appears on the active Hot List, suggesting heightened community monitoring and concern. The combination of the HIGH severity rating, active tracking status, and the demonstrated memory corruption evidence warrants immediate patching of affected systems to Firefox 150 and Thunderbird 150.