Detection rules › Sigma

New Remote Desktop Connection Initiated Via Mstsc.EXE

Severity
medium
Author
frack113
Source
upstream

Detects the usage of "mstsc.exe" with the "/v" flag to initiate a connection to a remote server. Adversaries may use valid accounts to log into a computer using the Remote Desktop Protocol (RDP). The adversary may then perform actions as the logged-on user.

MITRE ATT&CK coverage

TacticTechniques
Lateral MovementT1021.001 Remote Services: Remote Desktop Protocol

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation

Stages and Predicates

Stage 1: all of selection_img

or:
Image|endswith: '\mstsc.exe'
OriginalFileName: mstsc.exe

Stage 2: all of selection_cli

CommandLine|contains: ' /v:'

Stage 3: not 1 of filter_optional_wsl

CommandLine|contains: 'C:\ProgramData\Microsoft\WSL\wslg.rdp'
ParentImage: 'C:\Windows\System32\lxss\wslhost.exe'

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
CommandLinematch
  • /v:
  • C:\ProgramData\Microsoft\WSL\wslg.rdp corpus 2 (sigma 2)
Imageends_with
  • \mstsc.exe corpus 5 (sigma 5)
OriginalFileNameeq
  • mstsc.exe corpus 4 (sigma 4)
ParentImageeq
  • C:\Windows\System32\lxss\wslhost.exe corpus 2 (sigma 2)