Detectionhightest

Invoke-Obfuscation Via Stdin - Powershell

Detects Obfuscated Powershell via Stdin in Scripts

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Launch

Nikita Nazarov, oscd.communityCreated Mon Oct 12Updated Fri Apr 0586b896ba-ffa1-4fea-83e3-ee28a4c915c7windows

Log Source

WindowsPowerShell Script

ProductWindows← raw: windows

CategoryPowerShell Script← raw: ps_script

Definition

Requirements: Script Block Logging must be enabled

Detection Logic

detection:
    selection_4104:
        ScriptBlockText|re: '(?i)(set).*&&\s?set.*(environment|invoke|\$\{?input).*&&.*"'
    condition: selection_4104

False Positives

Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

References

Resolving title…

github.com

MITRE ATT&CK

Tactics

TA0005 · Defense Evasion TA0002 · Execution

Techniques

T1027 · Obfuscated Files or Information

Sub-techniques

T1059.001 · PowerShell

Rule Metadata

Rule ID

86b896ba-ffa1-4fea-83e3-ee28a4c915c7

Status

test

Level

high

Type

Detection

Created

Mon Oct 12

Modified

Fri Apr 05

Author

Nikita Nazarov, oscd.community

Path

rules/windows/powershell/powershell_script/posh_ps_invoke_obfuscation_via_stdin.yml

Raw Tags

attack.defense-evasionattack.t1027attack.executionattack.t1059.001

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