title: Suspicious Workstation Locking via Rundll32
id: 3b5b0213-0460-4e3f-8937-3abf98ff7dcc
status: test
description: Detects a suspicious call to the user32.dll function that locks the user workstation
references:
    - https://app.any.run/tasks/2aef9c63-f944-4763-b3ef-81eee209d128/
author: frack113
date: 2022-06-04
modified: 2023-02-09
tags:
    - attack.stealth
logsource:
    category: process_creation
    product: windows
detection:
    selection_call_img:
        - Image|endswith: '\rundll32.exe'
        - OriginalFileName: 'RUNDLL32.EXE'
    selection_call_parent:
        ParentImage|endswith: '\cmd.exe'
    selection_call_cli:
        CommandLine|contains: 'user32.dll,'
    selection_function:
        CommandLine|contains: 'LockWorkStation'
    condition: all of selection_*
falsepositives:
    - Scripts or links on the user desktop used to lock the workstation instead of Windows+L or the menu option
level: medium

title: Locked Workstation
id: 411742ad-89b0-49cb-a7b0-3971b5c1e0a4
status: stable
description: Detects locked workstation session events that occur automatically after a standard period of inactivity.
references:
    - https://www.cisecurity.org/controls/cis-controls-list/
    - https://www.pcisecuritystandards.org/documents/PCI_DSS_v3-2-1.pdf
    - https://nvlpubs.nist.gov/nistpubs/CSWP/NIST.CSWP.04162018.pdf
    - https://www.ultimatewindowssecurity.com/securitylog/encyclopedia/event.aspx?eventID=4800
author: Alexandr Yampolskyi, SOC Prime
date: 2019-03-26
modified: 2023-12-11
tags:
    - attack.impact
    # - CSC16
    # - CSC16.11
    # - ISO27002-2013 A.9.1.1
    # - ISO27002-2013 A.9.2.1
    # - ISO27002-2013 A.9.2.2
    # - ISO27002-2013 A.9.2.3
    # - ISO27002-2013 A.9.2.4
    # - ISO27002-2013 A.9.2.5
    # - ISO27002-2013 A.9.2.6
    # - ISO27002-2013 A.9.3.1
    # - ISO27002-2013 A.9.4.1
    # - ISO27002-2013 A.9.4.3
    # - ISO27002-2013 A.11.2.8
    # - PCI DSS 3.1 7.1
    # - PCI DSS 3.1 7.2
    # - PCI DSS 3.1 7.3
    # - PCI DSS 3.1 8.7
    # - PCI DSS 3.1 8.8
    # - NIST CSF 1.1 PR.AC-1
    # - NIST CSF 1.1 PR.AC-4
    # - NIST CSF 1.1 PR.AC-6
    # - NIST CSF 1.1 PR.AC-7
    # - NIST CSF 1.1 PR.PT-3
logsource:
    product: windows
    service: security
detection:
    selection:
        EventID: 4800
    condition: selection
falsepositives:
    - Likely
level: informational

title: ESXi Admin Permission Assigned To Account Via ESXCLI
id: 9691f58d-92c1-4416-8bf3-2edd753ec9cf
status: test
description: Detects execution of the "esxcli" command with the "system" and "permission" flags in order to assign admin permissions to an account.
references:
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-09-04
tags:
    - attack.persistence
    - attack.execution
    - attack.privilege-escalation
    - attack.t1059.012
    - attack.t1098
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'system'
        CommandLine|contains|all:
            - ' permission '
            - ' set'
            - 'Admin'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: high

title: ESXi Storage Information Discovery Via ESXCLI
id: f41dada5-3f56-4232-8503-3fb7f9cf2d60
status: test
description: Detects execution of the "esxcli" command with the "storage" flag in order to retrieve information about the storage status and other related information. Seen used by malware such as DarkSide and LockBit.
references:
    - https://www.trendmicro.com/en_us/research/21/e/darkside-linux-vms-targeted.html
    - https://www.trendmicro.com/en_us/research/22/a/analysis-and-Impact-of-lockbit-ransomwares-first-linux-and-vmware-esxi-variant.html
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_storage.html
author: Nasreddine Bencherchali (Nextron Systems), Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection_img:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'storage'
    selection_cli:
        CommandLine|contains:
            - ' get'
            - ' list'
    condition: all of selection_*
falsepositives:
    - Legitimate administration activities
# Note: level can be reduced to low in some envs
level: medium

title: ESXi Network Configuration Discovery Via ESXCLI
id: 33e814e0-1f00-4e43-9c34-31fb7ae2b174
status: test
description: Detects execution of the "esxcli" command with the "network" flag in order to retrieve information about the network configuration.
references:
    - https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_network.html
author: Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection_img:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'network'
    selection_cli:
        CommandLine|contains:
            - ' get'
            - ' list'
    condition: all of selection_*
falsepositives:
    - Legitimate administration activities
# Note: level can be reduced to low in some envs
level: medium

title: ESXi VSAN Information Discovery Via ESXCLI
id: d54c2f06-aca9-4e2b-81c9-5317858f4b79
status: test
description: Detects execution of the "esxcli" command with the "vsan" flag in order to retrieve information about virtual storage. Seen used by malware such as DarkSide.
references:
    - https://www.trendmicro.com/en_us/research/21/e/darkside-linux-vms-targeted.html
    - https://www.trendmicro.com/en_us/research/22/a/analysis-and-Impact-of-lockbit-ransomwares-first-linux-and-vmware-esxi-variant.html
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_vsan.html
author: Nasreddine Bencherchali (Nextron Systems), Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection_img:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'vsan'
    selection_cli:
        CommandLine|contains:
            - ' get'
            - ' list'
    condition: all of selection_*
falsepositives:
    - Legitimate administration activities
# Note: level can be reduced to low in some envs
level: medium

title: ESXi System Information Discovery Via ESXCLI
id: e80273e1-9faf-40bc-bd85-dbaff104c4e9
status: test
description: Detects execution of the "esxcli" command with the "system" flag in order to retrieve information about the different component of the system. Such as accounts, modules, NTP, etc.
references:
    - https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
author: Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection_img:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'system'
    selection_cli:
        CommandLine|contains:
            - ' get'
            - ' list'
    condition: all of selection_*
falsepositives:
    - Legitimate administration activities
level: medium

title: ESXi VM Kill Via ESXCLI
id: 2992ac4d-31e9-4325-99f2-b18a73221bb2
status: test
description: Detects execution of the "esxcli" command with the "vm" and "kill" flag in order to kill/shutdown a specific VM.
references:
    - https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_vm.html
    - https://www.secuinfra.com/en/techtalk/hide-your-hypervisor-analysis-of-esxiargs-ransomware/
    - https://www.trendmicro.com/en_us/research/22/e/new-linux-based-ransomware-cheerscrypt-targets-exsi-devices.html
author: Nasreddine Bencherchali (Nextron Systems), Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.execution
    - attack.impact
    - attack.t1059.012
    - attack.t1529
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/esxcli'
        CommandLine|contains|all:
            - 'vm process'
            - 'kill'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

title: ESXi Syslog Configuration Change Via ESXCLI
id: 38eb1dbb-011f-40b1-a126-cf03a0210563
status: test
description: Detects changes to the ESXi syslog configuration via "esxcli"
references:
    - https://support.solarwinds.com/SuccessCenter/s/article/Configure-ESXi-Syslog-to-LEM?language=en_US
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
author: Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.execution
    - attack.defense-impairment
    - attack.t1685
    - attack.t1690
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/esxcli'
        CommandLine|contains|all:
            - 'system'
            - 'syslog'
            - 'config'
        CommandLine|contains: ' set'
    condition: selection
falsepositives:
    - Legitimate administrative activities
level: medium

title: ESXi VM List Discovery Via ESXCLI
id: 5f1573a7-363b-4114-9208-ad7a61de46eb
status: test
description: Detects execution of the "esxcli" command with the "vm" flag in order to retrieve information about the installed VMs.
references:
    - https://www.crowdstrike.com/blog/hypervisor-jackpotting-ecrime-actors-increase-targeting-of-esxi-servers/
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_vm.html
    - https://www.secuinfra.com/en/techtalk/hide-your-hypervisor-analysis-of-esxiargs-ransomware/
    - https://www.trendmicro.com/en_us/research/22/e/new-linux-based-ransomware-cheerscrypt-targets-exsi-devices.html
author: Cedric Maurugeon
date: 2023-09-04
tags:
    - attack.discovery
    - attack.execution
    - attack.t1033
    - attack.t1007
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/esxcli'
        CommandLine|contains: 'vm process'
        CommandLine|endswith: ' list'
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

title: ESXi Account Creation Via ESXCLI
id: b28e4eb3-8bbc-4f0c-819f-edfe8e2f25db
status: test
description: Detects user account creation on ESXi system via esxcli
references:
    - https://developer.broadcom.com/xapis/esxcli-command-reference/7.0.0/namespace/esxcli_system.html
author: Cedric Maurugeon
date: 2023-08-22
tags:
    - attack.persistence
    - attack.execution
    - attack.t1136
    - attack.t1059.012
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/esxcli'
        CommandLine|contains|all:
            - 'system '
            - 'account '
            - 'add '
    condition: selection
falsepositives:
    - Legitimate administration activities
level: medium

title: UAC Bypass Using Windows Media Player - File
id: 68578b43-65df-4f81-9a9b-92f32711a951
status: test
description: Detects the pattern of UAC Bypass using Windows Media Player osksupport.dll (UACMe 32)
references:
    - https://github.com/hfiref0x/UACME
author: Christian Burkard (Nextron Systems)
date: 2021-08-23
modified: 2022-10-09
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    category: file_event
    product: windows
detection:
    selection1:
        TargetFilename|startswith: 'C:\Users\'
        TargetFilename|endswith: '\AppData\Local\Temp\OskSupport.dll'
    selection2:
        Image: 'C:\Windows\system32\DllHost.exe'
        TargetFilename: 'C:\Program Files\Windows Media Player\osk.exe'
    condition: 1 of selection*
falsepositives:
    - Unknown
level: high

title: UAC Bypass Using Windows Media Player - Process
id: 0058b9e5-bcd7-40d4-9205-95ca5a16d7b2
status: test
description: Detects the pattern of UAC Bypass using Windows Media Player osksupport.dll (UACMe 32)
references:
    - https://github.com/hfiref0x/UACME
author: Christian Burkard (Nextron Systems)
date: 2021-08-23
modified: 2024-12-01
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    category: process_creation
    product: windows
detection:
    selection_img_1:
        Image: 'C:\Program Files\Windows Media Player\osk.exe'
    selection_img_2:
        Image: 'C:\Windows\System32\cmd.exe'
        ParentCommandLine: '"C:\Windows\system32\mmc.exe" "C:\Windows\system32\eventvwr.msc" /s'
    selection_integrity:
        IntegrityLevel:
            - 'High'
            - 'System'
            - 'S-1-16-16384' # System
            - 'S-1-16-12288' # High
    condition: 1 of selection_img_* and selection_integrity
falsepositives:
    - Unknown
level: high

title: UAC Bypass Using Windows Media Player - Registry
id: 5f9db380-ea57-4d1e-beab-8a2d33397e93
status: test
description: Detects the pattern of UAC Bypass using Windows Media Player osksupport.dll (UACMe 32)
references:
    - https://github.com/hfiref0x/UACME
author: Christian Burkard (Nextron Systems)
date: 2021-08-23
modified: 2023-08-17
tags:
    - attack.privilege-escalation
    - attack.t1548.002
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|endswith: '\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Compatibility Assistant\Store\C:\Program Files\Windows Media Player\osk.exe'
        Details: 'Binary Data'
    condition: selection
falsepositives:
    - Unknown
level: high

title: Flash Player Update from Suspicious Location
id: 4922a5dd-6743-4fc2-8e81-144374280997
status: test
description: Detects a flashplayer update from an unofficial location
references:
    - https://gist.github.com/roycewilliams/a723aaf8a6ac3ba4f817847610935cfb
author: Florian Roth (Nextron Systems)
date: 2017-10-25
modified: 2022-08-08
tags:
    - attack.initial-access
    - attack.stealth
    - attack.t1189
    - attack.execution
    - attack.t1204.002
    - attack.t1036.005
logsource:
    category: proxy
detection:
    selection:
        - c-uri|contains: '/flash_install.php'
        - c-uri|endswith: '/install_flash_player.exe'
    filter:
        cs-host|endswith: '.adobe.com'
    condition: selection and not filter
falsepositives:
    - Unknown flash download locations
level: high