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{"bugzilla": {"description": "firefox: firefox: Sandbox escape via use-after-free in XPCOM", "id": "2562042", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2562042"}, "csaw": false, "cwe": "CWE-825", "details": ["Sandbox escape due to use-after-free in the XPCOM component. This vulnerability was fixed in Firefox 159 and Thunderbird 159.", "A flaw was found in Firefox. A use-after-free vulnerability in the Cross-Platform Component Object Model (XPCOM) component allows an attacker to achieve a sandbox escape. An attacker could exploit this memory corruption issue to break out of the browser's restricted security environment (sandbox) and execute arbitrary code on the host system."], "name": "CVE-2026-118021", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-10-27T14:06:04Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-118021\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-118021\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2076695\nhttps://www.mozilla.org/security/advisories/mfsa2026-118/"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[159,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}], "created": "2026-10-27T16:15:04.925027+00:00", "updated": "2026-11-05T19:45:15.820674+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}