{"id":"CVE-2026-78509","revision":"f5ae3a1b69074de389093abd471671e9","records":[{"revision":"f5ae3a1b69074de389093abd471671e9","observedAt":"2026-10-30T22:45:26.427+00:00","statement":{"source":"cve-program","id":"CVE-2026-78509","aliases":[],"title":"Microsoft Office Outlook Remote Code Execution Vulnerability","description":"Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.","state":0,"publishedAt":"2026-09-08T17:13:46.814+00:00","modifiedAt":"2026-10-30T21:52:10.46+00:00","affected":[{"ecosystem":"Vendor product","name":"Microsoft 365 Apps for Enterprise","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft 365 Apps for Enterprise\",\n                    \"platforms\": [\n                        \"32-bit Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.1\",\n                            \"lessThan\": \"16.0.20326.20138\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office 2019","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office 2019\",\n                    \"platforms\": [\n                        \"32-bit Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"19.0.0\",\n                            \"lessThan\": \"16.0.10417.20207\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office 365 for Mac","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office 365 for Mac\",\n                    \"versions\": [\n                        {\n                            \"version\": \"1.0.0\",\n                            \"lessThan\": \"16.113.26091433\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office LTSC 2021","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office LTSC 2021\",\n                    \"platforms\": [\n                        \"32-bit Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.1\",\n                            \"lessThan\": \"16.0.14334.20906\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office LTSC 2024","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office LTSC 2024\",\n                    \"platforms\": [\n                        \"32-bit Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.0\",\n                            \"lessThan\": \"16.0.17932.20976\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office LTSC for Mac 2021","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office LTSC for Mac 2021\",\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.1\",\n                            \"lessThan\": \"16.113.26091433\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Office LTSC for Mac 2024","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Office LTSC for Mac 2024\",\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.0\",\n                            \"lessThan\": \"16.113.26091433\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Microsoft Word 2016","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Microsoft\",\n                    \"product\": \"Microsoft Word 2016\",\n                    \"platforms\": [\n                        \"32-bit Systems\",\n                        \"x64-based Systems\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"16.0.1\",\n                            \"lessThan\": \"16.0.5569.1000\",\n                            \"versionType\": \"custom\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","score":9.8,"severity":"CRITICAL"}],"references":["https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-78509"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-78509","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-78509","identifiers":["CVE-2026-78509"]},"retained":false,"historicalAffected":[]}],"coverage":[]}