EXPLORE DETECTIONS
PowerShell - Connect To Internet With Hidden Window
The following analytic detects PowerShell commands using the WindowStyle parameter to hide the window while connecting to the Internet. This behavior is identified through Endpoint Detection and Response (EDR) telemetry, focusing on command-line executions that include variations of the WindowStyle parameter. This activity is significant because it attempts to bypass default PowerShell execution policies and conceal its actions, which is often indicative of malicious intent. If confirmed malicious, this could allow an attacker to execute commands stealthily, potentially leading to unauthorized data exfiltration or further compromise of the endpoint.
PowerShell 4104 Hunting
The following analytic identifies suspicious PowerShell execution using Script Block Logging (EventCode 4104). It leverages specific patterns and keywords within the ScriptBlockText field to detect potentially malicious activities. This detection is significant for SOC analysts as PowerShell is commonly used by attackers for various malicious purposes, including code execution, privilege escalation, and persistence. If confirmed malicious, this activity could allow attackers to execute arbitrary commands, exfiltrate data, or maintain long-term access to the compromised system, posing a severe threat to the organization's security.
Powershell COM Hijacking InprocServer32 Modification
The following analytic detects attempts to modify or add a Component Object Model (COM) entry to the InProcServer32 path within the registry using PowerShell. It leverages PowerShell ScriptBlock Logging (EventCode 4104) to identify suspicious script blocks that target the InProcServer32 registry path. This activity is significant because modifying COM objects can be used for persistence or privilege escalation by attackers. If confirmed malicious, this could allow an attacker to execute arbitrary code or maintain persistent access to the compromised system, posing a severe security risk.
Powershell Creating Thread Mutex
The following analytic detects the execution of PowerShell scripts using the `mutex` function via EventCode 4104. This detection leverages PowerShell Script Block Logging to identify scripts that create thread mutexes, a technique often used in obfuscated scripts to ensure only one instance runs on a compromised machine. This activity is significant as it may indicate the presence of sophisticated malware or persistence mechanisms. If confirmed malicious, the attacker could maintain exclusive control over a process, potentially leading to further exploitation or persistence within the environment.
Powershell Disable Security Monitoring
The following analytic identifies attempts to disable Windows Defender real-time behavior monitoring via PowerShell commands. It detects the use of specific `Set-MpPreference` parameters that disable various security features. This activity is significant as it is commonly used by malware such as RATs, bots, or Trojans to evade detection by disabling antivirus protections. If confirmed malicious, this action could allow an attacker to operate undetected, leading to potential data exfiltration, further system compromise, or persistent access within the environment.
PowerShell Domain Enumeration
The following analytic detects the execution of PowerShell commands used for domain enumeration, such as `get-netdomaintrust` and `get-adgroupmember`. It leverages PowerShell Script Block Logging (EventCode=4104) to capture and analyze the full command sent to PowerShell. This activity is significant as it often indicates reconnaissance efforts by an attacker to map out the domain structure and identify key users and groups. If confirmed malicious, this behavior could lead to further targeted attacks, privilege escalation, and unauthorized access to sensitive information within the domain.
PowerShell Enable PowerShell Remoting
The following analytic detects the use of the Enable-PSRemoting cmdlet, which allows PowerShell remoting on a local or remote computer. This detection leverages PowerShell Script Block Logging (EventCode 4104) to identify when this cmdlet is executed. Monitoring this activity is crucial as it can indicate an attacker enabling remote command execution capabilities on a compromised system. If confirmed malicious, this activity could allow an attacker to take control of the system remotely, execute commands, and potentially pivot to other systems within the network, leading to further compromise and lateral movement.
Powershell Enable SMB1Protocol Feature
The following analytic detects the enabling of the SMB1 protocol via `powershell.exe`. It leverages PowerShell script block logging (EventCode 4104) to identify the execution of the `Enable-WindowsOptionalFeature` cmdlet with the `SMB1Protocol` parameter. This activity is significant because enabling SMB1 can facilitate lateral movement and file encryption by ransomware, such as RedDot. If confirmed malicious, this action could allow an attacker to propagate through the network, encrypt files, and potentially disrupt business operations.
Powershell Execute COM Object
The following analytic detects the execution of a COM CLSID through PowerShell. It leverages EventCode 4104 and searches for specific script block text indicating the creation of a COM object. This activity is significant as it is commonly used by adversaries and malware, such as the Conti ransomware, to execute commands, potentially for privilege escalation or bypassing User Account Control (UAC). If confirmed malicious, this technique could allow attackers to gain elevated privileges or persist within the environment, posing a significant security risk.
Powershell Fileless Process Injection via GetProcAddress
The following analytic detects the use of `GetProcAddress` in PowerShell script blocks, leveraging PowerShell Script Block Logging (EventCode=4104). This method captures the full command sent to PowerShell, which is then logged in Windows event logs. The presence of `GetProcAddress` is unusual for typical PowerShell scripts and often indicates malicious activity, as many attack toolkits use it to achieve code execution. If confirmed malicious, this activity could allow an attacker to execute arbitrary code, potentially leading to system compromise. Analysts should review parallel processes and the entire logged script block for further investigation.
Powershell Fileless Script Contains Base64 Encoded Content
The following analytic detects the execution of PowerShell scripts containing Base64 encoded content, specifically identifying the use of `FromBase64String`. It leverages PowerShell Script Block Logging (EventCode=4104) to capture and analyze the full command sent to PowerShell. This activity is significant as Base64 encoding is often used by attackers to obfuscate malicious payloads, making it harder to detect. If confirmed malicious, this could lead to code execution, allowing attackers to run arbitrary commands and potentially compromise the system.
PowerShell Get LocalGroup Discovery
The following analytic identifies the use of the `get-localgroup` command executed via PowerShell or cmd.exe to enumerate local groups on an endpoint. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. Monitoring this activity is significant as it may indicate an attacker attempting to gather information about local group memberships, which can be a precursor to privilege escalation. If confirmed malicious, this activity could allow an attacker to identify and target privileged accounts, potentially leading to unauthorized access and control over the system.
Powershell Get LocalGroup Discovery with Script Block Logging
The following analytic detects the execution of the PowerShell cmdlet `get-localgroup` using PowerShell Script Block Logging (EventCode=4104). This method captures the full command sent to PowerShell, providing detailed visibility into script execution. Monitoring this activity is significant as it can indicate an attempt to enumerate local groups, which may be a precursor to privilege escalation or lateral movement. If confirmed malicious, an attacker could gain insights into group memberships, potentially leading to unauthorized access or privilege abuse. Review parallel processes and the entire script block for comprehensive analysis.
PowerShell Invoke CIMMethod CIMSession
The following analytic detects the creation of a New-CIMSession cmdlet followed by the use of the Invoke-CIMMethod cmdlet within PowerShell. It leverages PowerShell Script Block Logging to identify these specific cmdlets in the ScriptBlockText field. This activity is significant because it mirrors the behavior of the Invoke-WMIMethod cmdlet, often used for remote code execution via NTLMv2 pass-the-hash authentication. If confirmed malicious, this could allow an attacker to execute commands remotely, potentially leading to unauthorized access and control over targeted systems.
PowerShell Invoke WmiExec Usage
The following analytic detects the execution of the Invoke-WMIExec utility within PowerShell Script Block Logging (EventCode 4104). This detection leverages PowerShell script block logs to identify instances where the Invoke-WMIExec command is used. Monitoring this activity is crucial as it indicates potential lateral movement using WMI commands with NTLMv2 pass-the-hash authentication. If confirmed malicious, this activity could allow an attacker to execute commands remotely on target systems, potentially leading to further compromise and lateral spread within the network.
Powershell Load Module in Meterpreter
The following analytic detects the execution of suspicious PowerShell commands associated with Meterpreter modules, such as "MSF.Powershell" and "MSF.Powershell.Meterpreter". It leverages PowerShell Script Block Logging (EventCode=4104) to capture and analyze the full command sent to PowerShell. This activity is significant as it indicates potential post-exploitation actions, including credential dumping and persistence mechanisms. If confirmed malicious, an attacker could gain extensive control over the compromised system, escalate privileges, and maintain long-term access, posing a severe threat to the environment.
PowerShell Loading DotNET into Memory via Reflection
The following analytic detects the use of PowerShell scripts to load .NET assemblies into memory via reflection, a technique often used in malicious activities such as those by Empire and Cobalt Strike. It leverages PowerShell Script Block Logging (EventCode=4104) to capture and analyze the full command executed. This behavior is significant as it can indicate advanced attack techniques aiming to execute code in memory, bypassing traditional defenses. If confirmed malicious, this activity could lead to unauthorized code execution, privilege escalation, and persistent access within the environment.
Powershell Processing Stream Of Data
The following analytic detects suspicious PowerShell script execution involving compressed stream data processing, identified via EventCode 4104. It leverages PowerShell Script Block Logging to flag scripts using `IO.Compression`, `IO.StreamReader`, or decompression methods. This activity is significant as it often indicates obfuscated PowerShell or embedded .NET/binary execution, which are common tactics for evading detection. If confirmed malicious, this behavior could allow attackers to execute hidden code, escalate privileges, or maintain persistence within the environment.
Powershell Remote Services Add TrustedHost
The following analytic detects the execution of a PowerShell script that modifies the 'TrustedHosts' configuration via EventCode 4104. It leverages PowerShell Script Block Logging to identify commands targeting WSMan settings, specifically those altering or concatenating trusted hosts. This activity is significant as it can indicate attempts to manipulate remote connection settings, potentially allowing unauthorized remote access. If confirmed malicious, this could enable attackers to establish persistent remote connections, bypass security protocols, and gain unauthorized access to sensitive systems and data.
Powershell Remote Thread To Known Windows Process
The following analytic detects suspicious PowerShell processes attempting to inject code into critical Windows processes using CreateRemoteThread. It leverages Sysmon EventCode 8 to identify instances where PowerShell spawns threads in processes like svchost.exe, csrss.exe, and others. This activity is significant as it is commonly used by malware such as TrickBot and offensive tools like Cobalt Strike to execute malicious payloads, establish reverse shells, or download additional malware. If confirmed malicious, this behavior could lead to unauthorized code execution, privilege escalation, and persistent access within the environment.
Powershell Remove Windows Defender Directory
The following analytic detects a suspicious PowerShell command attempting to delete the Windows Defender directory. It leverages PowerShell Script Block Logging to identify commands containing "rmdir" and targeting the Windows Defender path. This activity is significant as it may indicate an attempt to disable or corrupt Windows Defender, a key security component. If confirmed malicious, this action could allow an attacker to bypass endpoint protection, facilitating further malicious activities without detection.
PowerShell Script Block With URL Chain
The following analytic identifies suspicious PowerShell script execution via EventCode 4104 that contains multiple URLs within a function or array. It leverages PowerShell operational logs to detect script blocks with embedded URLs, often indicative of obfuscated scripts or those attempting to download secondary payloads. This activity is significant as it may signal an attempt to execute malicious code or download additional malware. If confirmed malicious, this could lead to code execution, further system compromise, or data exfiltration. Review parallel processes and the full script block for additional context and related artifacts.
PowerShell Start or Stop Service
The following analytic identifies the use of PowerShell's Start-Service or Stop-Service cmdlets on an endpoint. It leverages PowerShell Script Block Logging to detect these commands. This activity is significant because attackers can manipulate services to disable or stop critical functions, causing system instability or disrupting business operations. If confirmed malicious, this behavior could allow attackers to disable security services, evade detection, or disrupt essential services, leading to potential system downtime and compromised security.
PowerShell Start-BitsTransfer
The following analytic detects the execution of the PowerShell command `Start-BitsTransfer`, which can be used for file transfers, including potential data exfiltration. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events and command-line arguments. This activity is significant because `Start-BitsTransfer` can be abused by adversaries to upload sensitive files to remote locations, posing a risk of data loss. If confirmed malicious, this could lead to unauthorized data exfiltration, compromising sensitive information and potentially leading to further exploitation of the network.