Detection rules › Splunk

Windows RDP Server Registry Entry Created

Author
Teoderick Contreras, Splunk
Source
upstream

This detection identifies the creation of registry keys under HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\Servers, which occur when a user initiates a Remote Desktop Protocol (RDP) connection using the built-in Windows RDP client (mstsc.exe). These registry entries store information about previously connected remote hosts, including usernames and display settings. Their creation is a strong indicator that an outbound RDP session was initiated from the system. While the presence of these keys is normal during legitimate RDP use, their appearance can be used to track remote access activity, especially in environments where RDP is tightly controlled. In post-compromise scenarios, these artifacts may be created by threat actors using RDP for lateral movement or command-and-control. Monitoring the creation of these registry entries can help defenders detect initial use of RDP from a compromised host, particularly when correlated with unusual user behavior, logon patterns, or network activity.

MITRE ATT&CK coverage

TacticTechniques
Lateral MovementT1021.001 Remote Services: Remote Desktop Protocol

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE Registry.action!="deleted" Registry.registry_path="*\\Microsoft\\Terminal Server Client\\Servers\\*" BY Registry.action, Registry.dest, Registry.process_guid, Registry.process_id, Registry.registry_hive, Registry.registry_path, Registry.registry_key_name, Registry.registry_value_data, Registry.registry_value_name, Registry.registry_value_type, Registry.status, Registry.user, Registry.vendor_product

Stage 2: search

search

Stage 3: search

search

Stage 4: search

search

Stage 5: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Registry.actionne
  • deleted
Registry.registry_patheq
  • "*\\Microsoft\\Terminal Server Client\\Servers\\*" corpus 2 (splunk 2)