resolve SigmaHQ#4821

nasbench · Jul 3, 2024 · c66f5e1 · c66f5e1
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diff --git a/rules/windows/file/file_event/file_event_win_susp_dpapi_backup_and_cert_export_ioc.yml b/rules/windows/file/file_event/file_event_win_susp_dpapi_backup_and_cert_export_ioc.yml
@@ -0,0 +1,31 @@
+title: DPAPI Backup Keys And Certificate Export Activity IOC
+id: 7892ec59-c5bb-496d-8968-e5d210ca3ac4
+status: experimental
+description: |
+    Detects file names with specific patterns seen generated and used by tools such as Mimikatz and DSInternals related to exported or stolen DPAPI backup keys and certificates.
+references:
+    - https://www.dsinternals.com/en/dpapi-backup-key-theft-auditing/
+    - https://github.com/MichaelGrafnetter/DSInternals/blob/39ee8a69bbdc1cfd12c9afdd7513b4788c4895d4/Src/DSInternals.Common/Data/DPAPI/DPAPIBackupKey.cs#L28-L32
+author: Nounou Mbeiri, Nasreddine Bencherchali (Nextron Systems)
+date: 2024/06/26
+tags:
+    - attack.t1555
+    - attack.t1552.004
+logsource:
+    product: windows
+    category: file_event
+detection:
+    selection:
+        TargetFilename|contains:
+            - 'ntds_capi_'
+            - 'ntds_legacy_'
+            - 'ntds_unknown_'
+        TargetFilename|endswith:
+            - '.cer'
+            - '.key'
+            - '.pfx'
+            - '.pvk'
+    condition: selection
+falsepositives:
+    - Unlikely
+level: high
diff --git a/rules/windows/powershell/powershell_script/posh_ps_dsinternals_cmdlets.yml b/rules/windows/powershell/powershell_script/posh_ps_dsinternals_cmdlets.yml
@@ -0,0 +1,90 @@
+title: DSInternals Suspicious PowerShell Cmdlets - ScriptBlock
+id: 846c7a87-8e14-4569-9d49-ecfd4276a01c
+related:
+    - id: 43d91656-a9b2-4541-b7e2-6a9bd3a13f4e
+      type: similar
+status: experimental
+description: |
+    Detects execution and usage of the DSInternals PowerShell module. Which can be used to perform what might be considered as suspicious activity such as dumping DPAPI backup keys or manipulating NTDS.DIT files.
+    The DSInternals PowerShell Module exposes several internal features of Active Directory and Azure Active Directory. These include FIDO2 and NGC key auditing, offline ntds.dit file manipulation, password auditing, DC recovery from IFM backups and password hash calculation.
+references:
+    - https://github.com/MichaelGrafnetter/DSInternals/blob/39ee8a69bbdc1cfd12c9afdd7513b4788c4895d4/Src/DSInternals.PowerShell/DSInternals.psd1
+author: Nasreddine Bencherchali (Nextron Systems)
+date: 2024/06/26
+tags:
+    - attack.execution
+    - attack.t1059.001
+logsource:
+    product: windows
+    category: ps_script
+    definition: 'Requirements: Script Block Logging must be enabled'
+detection:
+    selection:
+        ScriptBlockText|contains:
+            - 'Add-ADDBSidHistory'
+            - 'Add-ADNgcKey'
+            - 'Add-ADReplNgcKey'
+            - 'ConvertFrom-ADManagedPasswordBlob'
+            - 'ConvertFrom-GPPrefPassword'
+            - 'ConvertFrom-ManagedPasswordBlob'
+            - 'ConvertFrom-UnattendXmlPassword'
+            - 'ConvertFrom-UnicodePassword'
+            - 'ConvertTo-AADHash'
+            - 'ConvertTo-GPPrefPassword'
+            - 'ConvertTo-KerberosKey'
+            - 'ConvertTo-LMHash'
+            - 'ConvertTo-MsoPasswordHash'
+            - 'ConvertTo-NTHash'
+            - 'ConvertTo-OrgIdHash'
+            - 'ConvertTo-UnicodePassword'
+            - 'Disable-ADDBAccount'
+            - 'Enable-ADDBAccount'
+            - 'Get-ADDBAccount'
+            - 'Get-ADDBBackupKey'
+            - 'Get-ADDBDomainController'
+            - 'Get-ADDBGroupManagedServiceAccount'
+            - 'Get-ADDBKdsRootKey'
+            - 'Get-ADDBSchemaAttribute'
+            - 'Get-ADDBServiceAccount'
+            - 'Get-ADDefaultPasswordPolicy'
+            - 'Get-ADKeyCredential' # Covers 'Get-ADKeyCredentialLink'
+            - 'Get-ADPasswordPolicy'
+            - 'Get-ADReplAccount'
+            - 'Get-ADReplBackupKey'
+            - 'Get-ADReplicationAccount'
+            - 'Get-ADSIAccount'
+            - 'Get-AzureADUserEx'
+            - 'Get-BootKey'
+            - 'Get-KeyCredential'
+            - 'Get-LsaBackupKey'
+            - 'Get-LsaPolicy' # Covers 'Get-LsaPolicyInformation'
+            - 'Get-SamPasswordPolicy'
+            - 'Get-SysKey'
+            - 'Get-SystemKey'
+            - 'New-ADDBRestoreFromMediaScript'
+            - 'New-ADKeyCredential' # Covers 'New-ADKeyCredentialLink'
+            - 'New-ADNgcKey'
+            - 'New-NTHashSet'
+            - 'Remove-ADDBObject'
+            - 'Save-DPAPIBlob'
+            - 'Set-ADAccountPasswordHash'
+            - 'Set-ADDBAccountPassword' # Covers 'Set-ADDBAccountPasswordHash'
+            - 'Set-ADDBBootKey'
+            - 'Set-ADDBDomainController'
+            - 'Set-ADDBPrimaryGroup'
+            - 'Set-ADDBSysKey'
+            - 'Set-AzureADUserEx'
+            - 'Set-LsaPolicy' # Covers 'Set-LSAPolicyInformation'
+            - 'Set-SamAccountPasswordHash'
+            - 'Set-WinUserPasswordHash'
+            - 'Test-ADDBPasswordQuality'
+            - 'Test-ADPasswordQuality'
+            - 'Test-ADReplPasswordQuality'
+            - 'Test-PasswordQuality'
+            - 'Unlock-ADDBAccount'
+            - 'Write-ADNgcKey'
+            - 'Write-ADReplNgcKey'
+    condition: selection
+falsepositives:
+    - Legitimate usage of DSInternals for administration or audit purpose.
+level: high
diff --git a/rules/windows/process_creation/proc_creation_win_hktl_sharp_dpapi_execution.yml b/rules/windows/process_creation/proc_creation_win_hktl_sharp_dpapi_execution.yml
@@ -0,0 +1,50 @@
+title: HackTool - SharpDPAPI Execution
+id: c7d33b50-f690-4b51-8cfb-0fb912a31e57
+status: experimental
+description: |
+    Detects the execution of the SharpDPAPI tool based on CommandLine flags and PE metadata.
+    SharpDPAPI is a C# port of some DPAPI functionality from the Mimikatz project.
+references:
+    - https://github.com/GhostPack/SharpDPAPI
+author: Nasreddine Bencherchali (Nextron Systems)
+date: 2024/06/26
+tags:
+    - attack.privilege_escalation
+    - attack.defense_evasion
+    - attack.t1134.001
+    - attack.t1134.003
+logsource:
+    product: windows
+    category: process_creation
+detection:
+    selection_img:
+        - Image|endswith: '\SharpDPAPI.exe'
+        - OriginalFileName: 'SharpDPAPI.exe'
+    selection_other_cli:
+        CommandLine|contains:
+            - ' backupkey '
+            - ' blob '
+            - ' certificates '
+            - ' credentials '
+            - ' keepass '
+            - ' masterkeys '
+            - ' rdg '
+            - ' vaults '
+    selection_other_options_guid:
+        CommandLine|contains|all:
+            - ' {'
+            - '}:'
+    selection_other_options_flags:
+        CommandLine|contains:
+            - ' /file:'
+            - ' /machine'
+            - ' /mkfile:'
+            - ' /password:'
+            - ' /pvk:'
+            - ' /server:'
+            - ' /target:'
+            - ' /unprotect'
+    condition: selection_img or (selection_other_cli and 1 of selection_other_options_*)
+falsepositives:
+    - Unknown
+level: high
diff --git a/rules/windows/process_creation/proc_creation_win_powershell_dsinternals_cmdlets.yml b/rules/windows/process_creation/proc_creation_win_powershell_dsinternals_cmdlets.yml
@@ -0,0 +1,89 @@
+title: DSInternals Suspicious PowerShell Cmdlets
+id: 43d91656-a9b2-4541-b7e2-6a9bd3a13f4e
+related:
+    - id: 846c7a87-8e14-4569-9d49-ecfd4276a01c
+      type: similar
+status: experimental
+description: |
+    Detects execution and usage of the DSInternals PowerShell module. Which can be used to perform what might be considered as suspicious activity such as dumping DPAPI backup keys or manipulating NTDS.DIT files.
+    The DSInternals PowerShell Module exposes several internal features of Active Directory and Azure Active Directory. These include FIDO2 and NGC key auditing, offline ntds.dit file manipulation, password auditing, DC recovery from IFM backups and password hash calculation.
+references:
+    - https://github.com/MichaelGrafnetter/DSInternals/blob/39ee8a69bbdc1cfd12c9afdd7513b4788c4895d4/Src/DSInternals.PowerShell/DSInternals.psd1
+author: Nasreddine Bencherchali (Nextron Systems), Nounou Mbeiri
+date: 2024/06/26
+tags:
+    - attack.execution
+    - attack.t1059.001
+logsource:
+    product: windows
+    category: process_creation
+detection:
+    selection:
+        CommandLine|contains:
+            - 'Add-ADDBSidHistory'
+            - 'Add-ADNgcKey'
+            - 'Add-ADReplNgcKey'
+            - 'ConvertFrom-ADManagedPasswordBlob'
+            - 'ConvertFrom-GPPrefPassword'
+            - 'ConvertFrom-ManagedPasswordBlob'
+            - 'ConvertFrom-UnattendXmlPassword'
+            - 'ConvertFrom-UnicodePassword'
+            - 'ConvertTo-AADHash'
+            - 'ConvertTo-GPPrefPassword'
+            - 'ConvertTo-KerberosKey'
+            - 'ConvertTo-LMHash'
+            - 'ConvertTo-MsoPasswordHash'
+            - 'ConvertTo-NTHash'
+            - 'ConvertTo-OrgIdHash'
+            - 'ConvertTo-UnicodePassword'
+            - 'Disable-ADDBAccount'
+            - 'Enable-ADDBAccount'
+            - 'Get-ADDBAccount'
+            - 'Get-ADDBBackupKey'
+            - 'Get-ADDBDomainController'
+            - 'Get-ADDBGroupManagedServiceAccount'
+            - 'Get-ADDBKdsRootKey'
+            - 'Get-ADDBSchemaAttribute'
+            - 'Get-ADDBServiceAccount'
+            - 'Get-ADDefaultPasswordPolicy'
+            - 'Get-ADKeyCredential' # Covers 'Get-ADKeyCredentialLink'
+            - 'Get-ADPasswordPolicy'
+            - 'Get-ADReplAccount'
+            - 'Get-ADReplBackupKey'
+            - 'Get-ADReplicationAccount'
+            - 'Get-ADSIAccount'
+            - 'Get-AzureADUserEx'
+            - 'Get-BootKey'
+            - 'Get-KeyCredential'
+            - 'Get-LsaBackupKey'
+            - 'Get-LsaPolicy' # Covers 'Get-LsaPolicyInformation'
+            - 'Get-SamPasswordPolicy'
+            - 'Get-SysKey'
+            - 'Get-SystemKey'
+            - 'New-ADDBRestoreFromMediaScript'
+            - 'New-ADKeyCredential' # Covers 'New-ADKeyCredentialLink'
+            - 'New-ADNgcKey'
+            - 'New-NTHashSet'
+            - 'Remove-ADDBObject'
+            - 'Save-DPAPIBlob'
+            - 'Set-ADAccountPasswordHash'
+            - 'Set-ADDBAccountPassword' # Covers 'Set-ADDBAccountPasswordHash'
+            - 'Set-ADDBBootKey'
+            - 'Set-ADDBDomainController'
+            - 'Set-ADDBPrimaryGroup'
+            - 'Set-ADDBSysKey'
+            - 'Set-AzureADUserEx'
+            - 'Set-LsaPolicy' # Covers 'Set-LSAPolicyInformation'
+            - 'Set-SamAccountPasswordHash'
+            - 'Set-WinUserPasswordHash'
+            - 'Test-ADDBPasswordQuality'
+            - 'Test-ADPasswordQuality'
+            - 'Test-ADReplPasswordQuality'
+            - 'Test-PasswordQuality'
+            - 'Unlock-ADDBAccount'
+            - 'Write-ADNgcKey'
+            - 'Write-ADReplNgcKey'
+    condition: selection
+falsepositives:
+    - Legitimate usage of DSInternals for administration or audit purpose.
+level: high