Emerging Threatcriticaltest

Mint Sandstorm - AsperaFaspex Suspicious Process Execution

Detects suspicious execution from AsperaFaspex as seen used by Mint Sandstorm

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Launch
Nasreddine Bencherchali (Nextron Systems), MSTICCreated Thu Apr 20Updated Sun Oct 1991048c0d-5b81-4b85-a099-c9ee4fb879792023
Emerging Threat
Active Threat

Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.

Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic
Detection Logic15 selectors
detection:
    selection_parent:
        ParentImage|contains|all:
            - 'aspera'
            - '\ruby'
    selection_special_child_powershell_img:
        Image|endswith:
            - '\powershell.exe'
            - '\powershell_ise.exe'
    selection_special_child_powershell_cli:
        - CommandLine|contains:
              - ' echo '
              - '-dumpmode'
              - '-ssh'
              - '.dmp'
              - 'add-MpPreference'
              - 'adscredentials'
              - 'bitsadmin'
              - 'certutil'
              - 'csvhost.exe'
              - 'DownloadFile'
              - 'DownloadString'
              - 'dsquery'
              - 'ekern.exe'
              - 'FromBase64String'
              - 'iex '
              - 'iex('
              - 'Invoke-Expression'
              - 'Invoke-WebRequest'
              - 'localgroup administrators'
              - 'o365accountconfiguration'
              - 'samaccountname='
              - 'set-MpPreference'
              - 'svhost.exe'
              - 'System.IO.Compression'
              - 'System.IO.MemoryStream'
              - 'usoprivate'
              - 'usoshared'
              - 'whoami'
        - CommandLine|re:
              - '[-/–][Ee^]{1,2}[ncodema^]*\s[A-Za-z0-9+/=]{15,}'
              - 'net\s+user'
              - 'net\s+group'
              - 'query\s+session'
    selection_special_child_lsass_1:
        CommandLine|contains: 'lsass'
    selection_special_child_lsass_2:
        CommandLine|contains:
            - 'procdump'
            - 'tasklist'
            - 'findstr'
    selection_child_wget:
        Image|endswith: '\wget.exe'
        CommandLine|contains: 'http'
    selection_child_curl:
        Image|endswith: '\curl.exe'
        CommandLine|contains: 'http'
    selection_child_script:
        CommandLine|contains:
            - 'E:jscript'
            - 'e:vbscript'
    selection_child_localgroup:
        CommandLine|contains|all:
            - 'localgroup Administrators'
            - '/add'
    selection_child_net:
        CommandLine|contains: 'net' # Covers net1
        CommandLine|contains|all:
            - 'user'
            - '/add'
    selection_child_reg:
        - CommandLine|contains|all:
              - 'reg add'
              - 'DisableAntiSpyware'
              - '\Microsoft\Windows Defender'
        - CommandLine|contains|all:
              - 'reg add'
              - 'DisableRestrictedAdmin'
              - 'CurrentControlSet\Control\Lsa'
    selection_child_wmic_1:
        CommandLine|contains|all:
            - 'wmic'
            - 'process call create'
    selection_child_wmic_2:
        CommandLine|contains|all:
            - 'wmic'
            - 'delete'
            - 'shadowcopy'
    selection_child_vssadmin:
        CommandLine|contains|all:
            - 'vssadmin'
            - 'delete'
            - 'shadows'
    selection_child_wbadmin:
        CommandLine|contains|all:
            - 'wbadmin'
            - 'delete'
            - 'catalog'
    condition: selection_parent and (all of selection_special_child_powershell_* or all of selection_special_child_lsass_* or 1 of selection_child_*)
False Positives
Unlikely

False positives are unlikely for most environments. High confidence detection.

MITRE ATT&CK

Other

detection.emerging-threats
Rule Metadata
Rule ID
91048c0d-5b81-4b85-a099-c9ee4fb87979
Status
test
Level
critical
Type
Emerging Threat
Created
Thu Apr 20
Modified
Sun Oct 19
Path
rules-emerging-threats/2023/TA/Mint-Sandstorm/proc_creation_win_apt_mint_sandstorm_aspera_faspex_susp_child_process.yml
Raw Tags
attack.executiondetection.emerging-threats
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