Detection rules › Sigma

Suspicious Executable File Creation

Status
test
Severity
high
Log source
category file_event, product windows
Author
frack113
Source
github.com/SigmaHQ/sigma

Detect creation of suspicious executable file names. Some strings look for suspicious file extensions, others look for filenames that exploit unquoted service paths.

MITRE ATT&CK coverage

TacticTechniques
Stealth

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 11: FileCreate

Rule body

title: Suspicious Executable File Creation
id: 74babdd6-a758-4549-9632-26535279e654
status: test
description: |
    Detect creation of suspicious executable file names.
    Some strings look for suspicious file extensions, others look for filenames that exploit unquoted service paths.
references:
    - https://medium.com/@SumitVerma101/windows-privilege-escalation-part-1-unquoted-service-path-c7a011a8d8ae
    - https://app.any.run/tasks/76c69e2d-01e8-49d9-9aea-fb7cc0c4d3ad/
author: frack113
date: 2022-09-05
modified: 2023-12-11
tags:
    - attack.stealth
    - attack.t1564
logsource:
    product: windows
    category: file_event
detection:
    selection:
        TargetFilename|endswith:
            - ':\$Recycle.Bin.exe'
            - ':\Documents and Settings.exe'
            - ':\MSOCache.exe'
            - ':\PerfLogs.exe'
            - ':\Recovery.exe'
            - '.bat.exe'
            - '.sys.exe'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetFilename|endswith:
        - ':\$Recycle.Bin.exe'
        - ':\Documents and Settings.exe'
        - ':\MSOCache.exe'
        - ':\PerfLogs.exe'
        - ':\Recovery.exe'
        - '.bat.exe'
        - '.sys.exe'

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
TargetFilenameends_with
  • .bat.exe
  • .sys.exe
  • :\$Recycle.Bin.exe
  • :\Documents and Settings.exe
  • :\MSOCache.exe
  • :\PerfLogs.exe
  • :\Recovery.exe
field:"TargetFilename" kind:ends_with