Sigma rule: Security Software Discovery Via Powershell Script

Rule

Title

Security Software Discovery Via Powershell Script

Status

test

Level

medium

Author

frack113, Anish Bogati, Nasreddine Bencherchali (Nextron Systems)

Date

2021-12-16

Modified

2023-10-24

File

rules/windows/powershell/powershell_script/posh_ps_get_process_security_software_discovery.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

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

Log source

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_*

False positives (as the rule lists them)

• 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

Tags

• attack.discovery
• attack.t1518.001

MITRE ATT&CK ids this rule names

• T1518.001

References

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1518.001/T1518.001.md#atomic-test-2---security-software-discovery---powershell

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_get_process_security_software_discovery.yml