Detection rules › Sigma

Potentially Suspicious Compression Tool Parameters

Status
test
Severity
medium
Log source
category process_creation, product windows
Author
Florian Roth (Nextron Systems), Samir Bousseaden
Source
github.com/SigmaHQ/sigma

Detects potentially suspicious command line arguments of common data compression tools

MITRE ATT&CK coverage

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: Potentially Suspicious Compression Tool Parameters
id: 27a72a60-7e5e-47b1-9d17-909c9abafdcd
status: test
description: Detects potentially suspicious command line arguments of common data compression tools
references:
    - https://twitter.com/SBousseaden/status/1184067445612535811
author: Florian Roth (Nextron Systems), Samir Bousseaden
date: 2019-10-15
modified: 2023-08-29
tags:
    - attack.collection
    - attack.t1560.001
    - detection.threat-hunting
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        OriginalFileName:
            - '7z*.exe'
            - '*rar.exe'
            - '*Command*Line*RAR*'
        CommandLine|contains:
            - ' -p'
            - ' -ta'
            - ' -tb'
            - ' -sdel'
            - ' -dw'
            - ' -hp'
    filter_main_generic:
        ParentImage|contains:
            - ':\Program Files\'
            - ':\Program Files (x86)\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    OriginalFileName:
        - '7z*.exe'
        - '*rar.exe'
        - '*Command*Line*RAR*'
    CommandLine|contains:
        - ' -p'
        - ' -ta'
        - ' -tb'
        - ' -sdel'
        - ' -dw'
        - ' -hp'

Stage 2: not filter_main_generic

filter_main_generic:
    ParentImage|contains:
        - ':\Program Files\'
        - ':\Program Files (x86)\'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
ParentImagematch:\Program Files (x86)\excludes:ParentImage field:"ParentImage" value:":\Program Files (x86)\"
ParentImagematch:\Program Files\excludes:ParentImage field:"ParentImage" value:":\Program Files\"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
CommandLinematch
  • -dw
  • -hp corpus 4 (sigma 4)
  • -p corpus 4 (sigma 4)
  • -sdel
  • -ta
  • -tb
field:"CommandLine" kind:match
OriginalFileNamewildcard
  • *Command*Line*RAR*
  • *rar.exe
  • 7z*.exe
field:"OriginalFileName" kind:wildcard