{"id":"CVE-2026-50517","title":"Microsoft M365 Copilot Remote Code Execution Vulnerability","summary":"Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.","severity":"critical","cvss":9.9,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C","cvssSource":"cna","cwe":["CWE-502"],"vendor":"Microsoft","product":"Microsoft 365 Copilot","affected":["365_copilot -"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-07-24T00:00:00+00:00"},"published":"2026-07-24","updated":"2026-09-17","sourceUpdated":"2026-09-17T22:34:31.553Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-50517","references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50517","label":"Microsoft M365 Copilot Remote Code Execution Vulnerability"}],"tags":["cve.org"],"epss":0.01694,"epssPercentile":0.76113,"ingestedAt":"2026-09-08T17:06:31.893Z","slug":"CVE-2026-50517","body":"## Overview\n\nDeserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.\n\n## Affected\n\n- `365_copilot -`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":55,"depthScoreParts":{"impact":54.5,"likelihood":0.3,"exploitation":0,"ransomware":0},"changes":[]}