Security Software Discovery Via Powershell Script

SIGMA detection rule by frack113, Anish Bogati, Nasreddine Bencherchali (Nextron Systems) · NOASSERTION

Detects calls to "get-process" where the output is piped to a "where-object" filter to search for security solution processes. Adversaries may attempt to get a listing of security software, configurations, defensive tools, and sensors that are installed on a system or in a cloud environment. This may include things such as firewall rules and anti-virus

title: Security Software Discovery Via Powershell Script
id: 904e8e61-8edf-4350-b59c-b905fc8e810c
status: test
description: |
    Detects calls to "get-process" where the output is piped to a "where-object" filter to search for security solution processes.
    Adversaries may attempt to get a listing of security software, configurations, defensive tools, and sensors that are installed on a system or in a cloud environment. This may include things such as firewall rules and anti-virus
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1518.001/T1518.001.md#atomic-test-2---security-software-discovery---powershell
author: frack113, Anish Bogati, Nasreddine Bencherchali (Nextron Systems)
date: 2021-12-16
modified: 2023-10-24
tags:
    - attack.discovery
    - attack.t1518.001
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_cmdlet:
        ScriptBlockText|contains:
            - 'get-process | \?'
            - 'get-process | where'
            - 'gps | \?'
            - 'gps | where'
    selection_field:
        ScriptBlockText|contains:
            - 'Company -like'
            - 'Description -like'
            - 'Name -like'
            - 'Path -like'
            - 'Product -like'
    selection_keywords:
        ScriptBlockText|contains:
            # Note: These strings are using wildcard assuming the search is using the "-like" operator.
            #       You can add specific variant with the actual process names to increase coverage
            - '\*avira\*'
            - '\*carbonblack\*'
            - '\*cylance\*'
            - '\*defender\*'
            - '\*kaspersky\*'
            - '\*malware\*'
            - '\*sentinel\*'
            - '\*symantec\*'
            - '\*virus\*'
    condition: all of selection_*
falsepositives:
    - False positives might occur due to the nature of the ScriptBlock being ingested as a big blob. Initial tuning is required.
    - As the "selection_cmdlet" is common in scripts the matching engine might slow down the search. Change into regex or a more accurate string to avoid heavy resource consumption if experienced
level: medium
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_get_process_security_software_discovery/info.yml

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

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Executable code, not a declarative rule

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