Suspicious SysAidServer Child

SIGMA detection rule by Florian Roth (Nextron Systems) · NOASSERTION

Detects suspicious child processes of SysAidServer (as seen in MERCURY threat actor intrusions)

title: Suspicious SysAidServer Child
id: 60bfeac3-0d35-4302-8efb-1dd16f715bc6
status: test
description: Detects suspicious child processes of SysAidServer (as seen in MERCURY threat actor intrusions)
references:
    - https://www.microsoft.com/security/blog/2022/08/25/mercury-leveraging-log4j-2-vulnerabilities-in-unpatched-systems-to-target-israeli-organizations/
author: Florian Roth (Nextron Systems)
date: 2022-08-26
tags:
    - attack.lateral-movement
    - attack.t1210
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith:
            - '\java.exe'
            - '\javaw.exe'
        ParentCommandLine|contains: 'SysAidServer'
    condition: selection
falsepositives:
    - Unknown
level: medium

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

43cd2fe6-caf0-4dd6-898f-f285f259a077

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

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