{"id":"CVE-2026-56156","aliases":["EUVD-2026-44232","GHSA-4v4x-hh7w-55p3"],"status":"published","title":"Microsoft Excel Remote Code Execution Vulnerability","description":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","severity":{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00466,"percentile":0.40715,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-122"],"published":"2026-07-14T17:09:12Z","modified":"2026-11-01T17:36:44Z","products":[{"vendor":"microsoft","product":"365_apps"},{"vendor":"microsoft","product":"microsoft 365 apps for enterprise"},{"vendor":"microsoft","product":"microsoft office 365 for mac"},{"vendor":"microsoft","product":"microsoft office ltsc 2021"},{"vendor":"microsoft","product":"microsoft office ltsc 2024"},{"vendor":"microsoft","product":"microsoft office ltsc for mac 2021"},{"vendor":"microsoft","product":"microsoft office ltsc for mac 2024"},{"vendor":"microsoft","product":"microsoft_365"},{"vendor":"microsoft","product":"office_2021"},{"vendor":"microsoft","product":"office_2024"}],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56156","tags":["vendor-advisory","patch","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56156"},{"url":"https://github.com/advisories/GHSA-4v4x-hh7w-55p3"}],"sources":{"cve":[{"id":"CVE-2026-56156","title":"Microsoft Excel Remote Code Execution Vulnerability","description":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","status":"published","published":"2026-07-14T17:09:12.669Z","modified":"2026-11-01T17:36:44.363Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high","assessor":"cna"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T13:36:51.6229Z"}],"euvd":[{"id":"EUVD-2026-44232","description":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","status":"published","published":"2026-07-14T17:09:12Z","modified":"2026-11-01T17:36:44Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C","level":"high"}],"updated_at":"2026-11-02T16:58:46.970263Z"}],"ghsa":[{"id":"GHSA-4v4x-hh7w-55p3","title":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute...","description":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","status":"published","published":"2026-07-14T18:32:37Z","modified":"2026-07-14T18:32:43Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T15:09:30.715875Z"}],"nvd":[{"id":"CVE-2026-56156","description":"Heap-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code locally.","status":"published","published":"2026-07-14T18:18:22.537Z","modified":"2026-07-15T16:20:17.443Z","cvss":[{"version":"3.1","score":7.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-122"],"updated_at":"2026-11-02T14:12:29.489525Z"}]}}