Potential Remote Desktop Connection to Non-Domain Host

 1title: Potential Remote Desktop Connection to Non-Domain Host
 2id: ce5678bb-b9aa-4fb5-be4b-e57f686256ad
 3status: test
 4description: Detects logons using NTLM to hosts that are potentially not part of the domain.
 5references:
 6    - n/a
 7author: James Pemberton
 8date: 2020-05-22
 9modified: 2021-11-27
10tags:
11    - attack.command-and-control
12    - attack.t1219
13logsource:
14    product: windows
15    service: ntlm
16    definition: Requires events from Microsoft-Windows-NTLM/Operational
17detection:
18    selection:
19        EventID: 8001
20        TargetName|startswith: 'TERMSRV'
21    condition: selection
22fields:
23    - Computer
24    - UserName
25    - DomainName
26    - TargetName
27falsepositives:
28    - Host connections to valid domains, exclude these.
29    - Host connections not using host FQDN.
30    - Host connections to external legitimate domains.
31level: medium