Malicious Nishang PowerShell Commandlets

Severity: high
Author: Alec Costello
Source: upstream

Detects Commandlet names and arguments from the Nishang exploitation framework

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059.001` Command and Scripting Interpreter: PowerShell

Event coverage

Provider	Event ID	Title
PowerShell	4104	Creating Scriptblock text (MessageNumber of MessageTotal).

Stages and Predicates

Stage 1: `selection`

or:
ScriptBlockText|contains: 'Add-ConstrainedDelegationBackdoor'
ScriptBlockText|contains: Copy-VSS
ScriptBlockText|contains: Create-MultipleSessions
ScriptBlockText|contains: DNS_TXT_Pwnage
ScriptBlockText|contains: DataToEncode
ScriptBlockText|contains: Do-Exfiltration-Dns
ScriptBlockText|contains: Download-Execute-PS
ScriptBlockText|contains: 'DownloadAndExtractFromRemoteRegistry'
ScriptBlockText|contains: Download_Execute
ScriptBlockText|contains: DumpCerts
ScriptBlockText|contains: DumpCreds
ScriptBlockText|contains: DumpHashes
ScriptBlockText|contains: Enable-DuplicateToken
ScriptBlockText|contains: Enable-Duplication
ScriptBlockText|contains: Execute-Command-MSSQL
ScriptBlockText|contains: Execute-DNSTXT-Code
ScriptBlockText|contains: Execute-OnTime
ScriptBlockText|contains: ExetoText
ScriptBlockText|contains: ExfilOption
ScriptBlockText|contains: FakeDC
ScriptBlockText|contains: FireBuster
ScriptBlockText|contains: FireListener
ScriptBlockText|contains: 'Get-Information '
ScriptBlockText|contains: Get-PassHints
ScriptBlockText|contains: Get-WLAN-Keys
ScriptBlockText|contains: Get-Web-Credentials
ScriptBlockText|contains: Get-WebCredentials
ScriptBlockText|contains: HTTP-Backdoor
ScriptBlockText|contains: Invoke-AmsiBypass
ScriptBlockText|contains: Invoke-BruteForce
ScriptBlockText|contains: Invoke-CredentialsPhish
ScriptBlockText|contains: Invoke-Decode
ScriptBlockText|contains: Invoke-Encode
ScriptBlockText|contains: Invoke-Interceptor
ScriptBlockText|contains: Invoke-JSRatRegsvr
ScriptBlockText|contains: Invoke-JSRatRundll
ScriptBlockText|contains: Invoke-MimikatzWDigestDowngrade
ScriptBlockText|contains: Invoke-NetworkRelay
ScriptBlockText|contains: Invoke-PSGcat
ScriptBlockText|contains: Invoke-PowerShellIcmp
ScriptBlockText|contains: Invoke-PowerShellUdp
ScriptBlockText|contains: Invoke-Prasadhak
ScriptBlockText|contains: Invoke-PsGcatAgent
ScriptBlockText|contains: Invoke-SSIDExfil
ScriptBlockText|contains: Invoke-SessionGopher
ScriptBlockText|contains: LoggedKeys
ScriptBlockText|contains: Nishang
ScriptBlockText|contains: NotAllNameSpaces
ScriptBlockText|contains: OUT-DNSTXT
ScriptBlockText|contains: Out-CHM
ScriptBlockText|contains: Out-HTA
ScriptBlockText|contains: Out-RundllCommand
ScriptBlockText|contains: Out-SCF
ScriptBlockText|contains: Out-SCT
ScriptBlockText|contains: Out-Shortcut
ScriptBlockText|contains: Out-WebQuery
ScriptBlockText|contains: Out-Word
ScriptBlockText|contains: Parse_Keys
ScriptBlockText|contains: Password-List
ScriptBlockText|contains: Powerpreter
ScriptBlockText|contains: Remove-Persistence
ScriptBlockText|contains: Remove-PoshRat
ScriptBlockText|contains: Remove-Update
ScriptBlockText|contains: Run-EXEonRemote
ScriptBlockText|contains: Set-DCShadowPermissions
ScriptBlockText|contains: Set-RemotePSRemoting
ScriptBlockText|contains: Set-RemoteWMI
ScriptBlockText|contains: Shellcode32
ScriptBlockText|contains: Shellcode64
ScriptBlockText|contains: StringtoBase64
ScriptBlockText|contains: TexttoExe
ScriptBlockText|contains: exfill

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`ScriptBlockText`	match	`Add-ConstrainedDelegationBackdoor` `Copy-VSS` `Create-MultipleSessions` `DNS_TXT_Pwnage` `DataToEncode` `Do-Exfiltration-Dns` `Download-Execute-PS` `DownloadAndExtractFromRemoteRegistry` `Download_Execute` `DumpCerts` corpus 2 (sigma 2) `DumpCreds` corpus 2 (sigma 2) `DumpHashes` `Enable-DuplicateToken` `Enable-Duplication` `Execute-Command-MSSQL` `Execute-DNSTXT-Code` `Execute-OnTime` `ExetoText` `ExfilOption` `FakeDC` `FireBuster` `FireListener` `Get-Information` `Get-PassHints` `Get-WLAN-Keys` `Get-Web-Credentials` `Get-WebCredentials` `HTTP-Backdoor` `Invoke-AmsiBypass` `Invoke-BruteForce` `Invoke-CredentialsPhish` `Invoke-Decode` `Invoke-Encode` `Invoke-Interceptor` `Invoke-JSRatRegsvr` `Invoke-JSRatRundll` `Invoke-MimikatzWDigestDowngrade` `Invoke-NetworkRelay` `Invoke-PSGcat` `Invoke-PowerShellIcmp` `Invoke-PowerShellUdp` `Invoke-Prasadhak` `Invoke-PsGcatAgent` `Invoke-SSIDExfil` `Invoke-SessionGopher` `LoggedKeys` `Nishang` `NotAllNameSpaces` `OUT-DNSTXT` `Out-CHM` `Out-HTA` `Out-RundllCommand` `Out-SCF` `Out-SCT` `Out-Shortcut` `Out-WebQuery` `Out-Word` `Parse_Keys` `Password-List` `Powerpreter` `Remove-Persistence` `Remove-PoshRat` `Remove-Update` corpus 2 (sigma 2) `Run-EXEonRemote` `Set-DCShadowPermissions` `Set-RemotePSRemoting` `Set-RemoteWMI` `Shellcode32` `Shellcode64` `StringtoBase64` `TexttoExe` `exfill`

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.

Potential PowerShell Obfuscation via Invalid Escape Sequences [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via Backtick-Escaped Variable Expansion [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via Character Array Reconstruction [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via Concatenated Dynamic Command Invocation [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via High Numeric Character Proportion [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential Dynamic IEX Reconstruction via Environment Variables [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Dynamic IEX Reconstruction via Method String Access [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
PowerShell Obfuscation via Negative Index String Reversal [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via Reverse Keywords [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via String Concatenation [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via String Reordering [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)
Potential PowerShell Obfuscation via Special Character Overuse [elastic] (cross-vendor) (drops 1 filter this rule applies) (first-stage match only; downstream stages may differ)