Detection rules › Sigma

PSEXEC Remote Execution File Artefact

Status
test
Severity
high
Log source
product windows, category file_event
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects creation of the PSEXEC key file. Which is created anytime a PsExec command is executed. It gets written to the file system and will be recorded in the USN Journal on the target system

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 11FileCreate

Rule body yaml

title: PSEXEC Remote Execution File Artefact
id: 304afd73-55a5-4bb9-8c21-0b1fc84ea9e4
status: test
description: Detects creation of the PSEXEC key file. Which is created anytime a PsExec command is executed. It gets written to the file system and will be recorded in the USN Journal on the target system
references:
    - https://aboutdfir.com/the-key-to-identify-psexec/
    - https://twitter.com/davisrichardg/status/1616518800584704028
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-21
modified: 2023-02-23
tags:
    - attack.lateral-movement
    - attack.privilege-escalation
    - attack.execution
    - attack.persistence
    - attack.t1136.002
    - attack.t1543.003
    - attack.t1570
    - attack.s0029
logsource:
    category: file_event
    product: windows
detection:
    selection:
        TargetFilename|startswith: 'C:\Windows\PSEXEC-'
        TargetFilename|endswith: '.key'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|startswith: 'C:\Windows\PSEXEC-'
    TargetFilename|endswith: '.key'

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
TargetFilenameends_with
  • .key corpus 2 (sigma 2)
TargetFilenamestarts_with
  • C:\Windows\PSEXEC-