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{"bugzilla": {"description": "thunderbird: Thunderbird: Arbitrary code execution via malicious calendar invitation attachments", "id": "2527103", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2527103"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-59", "details": ["A flaw was found in Thunderbird. Malicious calendar invitations could use file URI attachments to launch local or network-hosted executables on Windows systems. This bypasses Thunderbird's built-in protections for executable attachments, potentially leading to arbitrary code execution. Additionally, the attachment could be disguised with a misleading filename, increasing the risk of exploitation."], "name": "CVE-2026-84637", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-09-01T21:25:08Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-84637\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-84637\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2043878\nhttps://www.mozilla.org/security/advisories/mfsa2026-78/"], "threat_severity": "Important"}