{
  "id": "4779",
  "source": "windows_security",
  "priority": "P3",
  "applicable_version": "Windows Server 2008 and later where the audit subcategory is enabled",
  "last_reviewed": "2026-07-13",
  "category": "Logon",
  "name": "A session was disconnected from a Window Station",
  "definition": "Windows Security Event ID 4779 records disconnection from an existing Terminal Services, Fast User Switching, or Hyper-V Enhanced Session desktop session.",
  "trigger_scenarios": "Microsoft documents that this event is generated when a user disconnects from an existing Terminal Services session or switches away from an existing desktop.",
  "key_fields": [
    {
      "field": "Account Name / Account Domain / Logon ID",
      "explanation": "The user and hexadecimal session identifier associated with the disconnect."
    },
    {
      "field": "Session Name",
      "explanation": "The terminal session name associated with the disconnect, commonly an RDP-Tcp session."
    },
    {
      "field": "Client Name / Client Address",
      "explanation": "The endpoint associated with the disconnected session."
    }
  ],
  "false_positives": [
    "Normal RDP disconnects, network drops, and users closing the RDP client are common.",
    "Fast User Switching and Hyper-V Enhanced Session disconnects can be benign."
  ],
  "related_event_ids": [
    "4778",
    "4624",
    "4634"
  ],
  "attck_mapping": [
    {
      "technique_id": "T1021.001",
      "technique_name": "Remote Services: Remote Desktop Protocol"
    }
  ],
  "detection_notes": "Investigate 4779 when Client Address belongs to an unusual external/VPN host and the same Logon ID later reconnects through 4778, especially for administrators. Microsoft documents Client Address and Session Name fields; repeated RDP-Tcp disconnect/reconnect cycles can preserve T1021.001 Remote Desktop Protocol access while reducing full logon visibility. Correlate with 4624 Type 10, 4648 explicit credentials, and commands run after reconnection.",
  "kql_snippet": "SecurityEvent\n| where EventID == 4779\n| project TimeGenerated, Computer, Account, SessionName, ClientAddress, LogonID",
  "spl_snippet": "index=wineventlog EventCode=4779 | table _time, host, Account_Name, Session_Name, Client_Address, Logon_ID",
  "sample_log": "EventID: 4779\nAccount Name: admin\nAccount Domain: CORP\nLogon ID: 0x169e9\nSession Name: RDP-Tcp#0\nClient Name: LAPTOP42\nClient Address: 10.42.42.211",
  "source_url": "https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4779",
  "route": "/windows-events/4779/",
  "canonical_url": "https://soceventlookup.com/windows-events/4779/",
  "json_url": "/api/events/windows-security/4779.json"
}