DeepBlueCLI – a PowerShell Module for Threat Hunting via Windows Event Logs
DeepBlueCLI – a PowerShell Module for Threat Hunting via Windows Event Logs
Eric Conrad, Backshore Communications, LLC
deepblue at backshore dot net
Twitter: @eric_conrad
Sample evtx files are in the .evtx directory
Usage:
.DeepBlue.ps1 <event log name> <evtx filename>
See the Set-ExecutionPolicy Readme if you receive a ‘running scripts is disabled on this system’ error.
Process local Windows security event log (PowerShell must be run as Administrator):
.DeepBlue.ps1
or:
.DeepBlue.ps1 -log security
Process local Windows system event log:
.DeepBlue.ps1 -log system
Process evtx file:
.DeepBlue.ps1 .evtxnew-user-security.evtx
Windows Event Logs processed
- Windows Security
- Windows System
- Windows Application
- Windows PowerShell
- Sysmon
Command Line Logs processed
See Logging setup section below for how to configure these logs
- Windows Security event ID 4688
- Windows PowerShell event IDs 4103 and 4104
- Sysmon event ID 1
Detected events
- Suspicious account behavior
- User creation
- User added to local/global/universal groups
- Password guessing (multiple logon failures, one account)
- Password spraying via failed logon (multiple logon failures, multiple accounts)
- Password spraying via explicit credentials
- Bloodhound (admin privileges assigned to the same account with multiple Security IDs)
- Command line/Sysmon/PowerShell auditing
- Long command lines
- Regex searches
- Obfuscated commands
- PowerShell launched via WMIC or PsExec
- PowerShell Net.WebClient Downloadstring
- Compressed/Base64 encoded commands (with automatic decompression/decoding)
- Unsigned EXEs or DLLs
- Service auditing
- Suspicious service creation
- Service creation errors
- Stopping/starting the Windows Event Log service (potential event log manipulation)
- Mimikatz
lsadump::sam
- EMET & Applocker Blocks
…and more
Examples
| Event | Command |
|---|---|
| Event log manipulation | .DeepBlue.ps1 .evtxdisablestop-eventlog.evtx |
| Metasploit native target (security) | .DeepBlue.ps1 .evtxmetasploit-psexec-native-target-security.evtx |
| Metasploit native target (system) | .DeepBlue.ps1 .evtxmetasploit-psexec-native-target-system.evtx |
| Metasploit PowerShell target (security) | .DeepBlue.ps1 .evtxmetasploit-psexec-powershell-target-security.evtx |
| Metasploit PowerShell target (system) | .DeepBlue.ps1 .evtxmetasploit-psexec-powershell-target-system.evtx |
Mimikatz lsadump::sam |
.DeepBlue.ps1 .evtxmimikatz-privesc-hashdump.evtx |
| New user creation | .DeepBlue.ps1 .evtxnew-user-security.evtx |
| Obfuscation (encoding) | .DeepBlue.ps1 .evtxPowershell-Invoke-Obfuscation-encoding-menu.evtx |
| Obfuscation (string) | .DeepBlue.ps1 .evtxPowershell-Invoke-Obfuscation-string-menu.evtx |
| Password guessing | .DeepBlue.ps1 .evtxsmb-password-guessing-security.evtx |
| Password spraying | .DeepBlue.ps1 .evtxpassword-spray.evtx |
| PowerSploit (security) | .DeepBlue.ps1 .evtxpowersploit-security.evtx |
| PowerSploit (system) | .DeepBlue.ps1 .evtxpowersploit-system.evtx |
| PSAttack | .DeepBlue.ps1 .evtxpsattack-security.evtx |
| User added to administrator group | .DeepBlue.ps1 .evtxnew-user-security.evtx |
Output
DeepBlueCLI outputs in PowerShell objects, allowing a variety of output methods and types, including JSON, HTML, CSV, etc.
For example:
| Output Type | Syntax |
|---|---|
| CSV | .DeepBlue.ps1 .evtxpsattack-security.evtx | ConvertTo-Csv |
| Format list (default) | .DeepBlue.ps1 .evtxpsattack-security.evtx | Format-List |
| Format table | .DeepBlue.ps1 .evtxpsattack-security.evtx | Format-Table |
| GridView | .DeepBlue.ps1 .evtxpsattack-security.evtx | Out-GridView |
| HTML | .DeepBlue.ps1 .evtxpsattack-security.evtx | ConvertTo-Html |
| JSON | .DeepBlue.ps1 .evtxpsattack-security.evtx | ConvertTo-Json |
| XML | .DeepBlue.ps1 .evtxpsattack-security.evtx | ConvertTo-Xml |
Logging setup
Security event 4688 (Command line auditing):
Enable Windows command-line auditing: https://support.microsoft.com/en-us/kb/3004375
Security event 4625 (Failed logons):
Requires auditing logon failures: https://technet.microsoft.com/en-us/library/cc976395.aspx
PowerShell auditing (PowerShell 5.0):
DeepBlueCLI uses module logging (PowerShell event 4103) and script block logging (4104). It does not use transcription.
See: https://www.fireeye.com/blog/threat-research/2016/02/greater_visibilityt.html
To get the PowerShell commandline (and not just script block) on Windows 7 through Windows 8.1, add the following to WindowsSystem32WindowsPowerShellv1.0profile.ps1
$LogCommandHealthEvent = $true
$LogCommandLifecycleEvent = $true
See the following for more information:
- https://logrhythm.com/blog/powershell-command-line-logging/
- http://hackerhurricane.blogspot.com/2014/11/i-powershell-logging-what-everyone.html
Thank you: @heinzarelli and @HackerHurricane
Sysmon
Install Sysmon from Sysinternals: https://docs.microsoft.com/en-us/sysinternals/downloads/sysmon
DeepBlue and DeepWhite currently use Sysmon events, 1, 6 and 7.
Log SHA256 hashes. Others are fine; DeepBlueCLI will use SHA256.
