Detection rules › Splunk

RDP Enabled (Sysmon)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

Detects if RDP service has been enabled on Windows host

MITRE ATT&CK coverage

References

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

id: '1106.1173'
title: RDP Enabled
description: 'Detects if RDP service has been enabled on Windows host -- Threat Actor
  Association: APT35/Phosphorus/Magic Hound, DarkSide, BlackMatter, FIN7, TA551, Wizard
  Spider, Yanluowang -- Software Association: BianLian, Black Basta, Conti, Hive,
  IcedID, Insekt, Lockbit, Nefilim, Ryuk Ransomware, Sodinokibi/REvil'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_sysmon` EventCode=1 ( ("reg.exe" AND
  TERM(add) AND TERM(fDenyTSConnections) AND TERM(REG_DWORD) AND TERM(/d) AND TERM(0)
  AND TERM(Terminal) AND TERM(Server) ) OR ("netsh.exe" AND TERM(remote) AND TERM(desktop)
  AND TERM(enable=yes)) ) | table _time, host, user process, process_*, parent_process,
  parent_process_* | bin span=1s | stats values(*) as * by _time, host '
techniques:
- defense-evasion:modify registry
- lateral-movement:remote services:remote desktop protocol
technique_id:
- T1112
- T1021.001
data_category:
- Windows Sysmon
references:
- https://pureinfotech.com/enable-remote-desktop-command-prompt-windows-10/

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_sysmon` EventCode=1 ( ("reg.exe" AND TERM(add) AND TERM(fDenyTSConnections) AND TERM(REG_DWORD) AND TERM(/d) AND TERM(0) AND TERM(Terminal) AND TERM(Server) ) OR ("netsh.exe" AND TERM(remote) AND TERM(desktop) AND TERM(enable=yes)) )

Stage 2: table

| table _time, host, user process, process_*, parent_process, parent_process_*

Stage 3: bucket

| bin span=1s

Stage 4: stats

| stats values(*) as * by _time, host

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
EventCodeeq
  • 1 corpus 237 (splunk 224, kusto 13)

Search terms

Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.

StageTerm
1"reg.exe"
1TERM
1add
1TERM
1fDenyTSConnections
1TERM
1REG_DWORD
1"/d"
1TERM
10
1TERM
1Terminal
1TERM
1Server
1"netsh.exe"
1TERM
1remote
1TERM
1desktop
1"enable=yes"