{
 "id": "CVE-2026-50517",
 "description": "Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.",
 "published": "2026-07-24",
 "last_modified": "2026-10-24",
 "vuln_status": "Analyzed",
 "cna": "secure@microsoft.com",
 "cvss": {
  "version": "3.1",
  "score": 9.9,
  "severity": "CRITICAL",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
  "source": "secure@microsoft.com"
 },
 "cwe": [
  "CWE-502"
 ],
 "products": [
  {
   "vendor": "microsoft",
   "product": "365_copilot",
   "versions_affected": null,
   "fixed_in": null,
   "product_id": "m365-copilot"
  }
 ],
 "category": "product",
 "surface": [
  "code_execution"
 ],
 "kev": null,
 "fix": {
  "status": "unknown",
  "version": null,
  "url": null
 },
 "references": [
  {
   "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50517",
   "source": "secure@microsoft.com",
   "tags": [
    "Vendor Advisory"
   ]
  }
 ],
 "related_agents": [
  "microsoft-microsoft-365-copilot-for-government"
 ],
 "related_incidents": [],
 "match": {
  "tests": [
   "A:cpe"
  ],
  "terms": [
   "m365-copilot:microsoft:365_copilot"
  ]
 },
 "status": "candidate",
 "note": null,
 "reviewer": null,
 "checked_on": null,
 "retrieved_on": "2026-10-26"
}