CVE-2026-8959

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{"bugzilla": {"description": "firefox: Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component", "id": "2479861", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2479861"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "status": "draft"}, "cwe": "CWE-653", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nSandbox escape due to incorrect boundary conditions in the Widget: Win32 component"], "name": "CVE-2026-8959", "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:10", "fix_state": "Affected", "package_name": "rhel10/firefox-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 6"}, {"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": "2026-05-19T12:29:55Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-8959\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-8959\nhttps://www.mozilla.org/security/advisories/mfsa2026-48/#CVE-2026-8959"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.11,141.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[151,*]"}}], "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": "2026-05-19T15:00:10.592211+00:00", "updated": "2026-05-22T02:15:06.441493+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}