CVE-2026-109740

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{"bugzilla": {"description": "firefox: firefox: Sandbox escape via incorrect boundary conditions in Win32 widget", "id": "2550404", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2550404"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.8", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-653", "details": ["A flaw was found in Firefox. Incorrect boundary condition handling in the Win32 widget component allows an attacker to escape the browser's restricted sandbox environment. An attacker who has compromised a sandboxed content process could exploit this vulnerability to achieve privilege escalation and execute arbitrary code on the underlying operating system."], "name": "CVE-2026-109740", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Will not fix", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Will not fix", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Will not fix", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Will not fix", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-10-13T12:29:26Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-109740\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-109740\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2057113\nhttps://www.mozilla.org/security/advisories/mfsa2026-106/\nhttps://www.mozilla.org/security/advisories/mfsa2026-108/"], "threat_severity": "Important"}

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