Detection rules › Sigma

PSexec application execution

Status
experimental
Severity
medium
Log source
category process_creation, product windows
Author
mdecrevoisier
Source
github.com/mdecrevoisier/SIGMA-detection-rules

Detects scenarios where an attacker installs and executes PSexec.

Known false positives

  • Administrator activity

MITRE ATT&CK coverage

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: PSexec application execution
description: Detects scenarios where an attacker installs and executes PSexec.
references:
- https://github.com/mdecrevoisier/EVTX-to-MITRE-Attack/tree/master/TA0008-Lateral%20Movement/T1021.002%20-SMB%20Windows%20Admin%20Shares
- https://attack.mitre.org/software/S0029/
- https://pentera.io/blog/135-is-the-new-145/
- https://nv2lt.github.io/windows/smb-psexec-smbexec-winexe-how-to/
- https://www.synacktiv.com/publications/traces-of-windows-remote-command-execution.html
tags:
- attack.execution
- attack.t1569.002
author: mdecrevoisier
status: experimental
logsource:
  product: windows
  category: process_creation
detection:
  selection_process_child:
    NewProcessName|endswith: \PSEXESVC.exe

  selection_process_parent:
    ParentProcessName|endswith: \PSEXESVC.exe
    Version: 2  # parent process name is available starting Windows 10 / Server 2016 and higher

  condition: selection_process_child or selection_process_parent
falsepositives:
- Administrator activity
level: medium

Stages and Predicates

Stage 0: condition

selection_process_child or selection_process_parent

Stage 1: selection_process_child

selection_process_child:
  NewProcessName|endswith: \PSEXESVC.exe

Stage 2: selection_process_parent

selection_process_parent:
  ParentProcessName|endswith: \PSEXESVC.exe
  Version: 2

Indicators

These rows show field, operator, and value matches.