Invoke-Obfuscation COMPRESS OBFUSCATION

testmedium
log source: windows · process_creationauthor Timur Zinniatullin, oscd.communitydate 2020-10-18
01

description

What this is, in brief.

Detects Obfuscated Powershell via COMPRESS OBFUSCATION

02

tags

attack.stealthattack.t1027attack.executionattack.t1059.001
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rule source (YAML)

title: Invoke-Obfuscation COMPRESS OBFUSCATION
id: 7eedcc9d-9fdb-4d94-9c54-474e8affc0c7
status: test
description: Detects Obfuscated Powershell via COMPRESS OBFUSCATION
references:
    - https://github.com/SigmaHQ/sigma/issues/1009 # (Task 19)
author: Timur Zinniatullin, oscd.community
date: 2020-10-18
modified: 2022-12-29
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        CommandLine|contains|all:
            - 'new-object'
            - 'text.encoding]::ascii'
        CommandLine|contains:
            - 'system.io.compression.deflatestream'
            - 'system.io.streamreader'
            - 'readtoend('
    condition: selection
falsepositives:
    - Unknown
level: medium
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detects techniques (2)

ATT&CK techniques this enables or maps to.

05

references

External citations — patches, advisories, analysis.