EXPLORE DETECTIONS
Windows PowerShell Process Implementing Manual Base64 Decoder
The following analytic identifies Windows PowerShell processes that implement a manual Base64 decoder. Threat actors often use Base64 encoding to obfuscate malicious payloads or commands within PowerShell scripts. By manually decoding Base64 strings, attackers can evade detection mechanisms that look for standard decoding functions like using the "-enc" flag or the "FromBase64String" function. This detection focuses on PowerShell processes that exhibit characteristics of manual Base64 decoding, such as the presence of specific string manipulation methods and bitwise operations. Security teams should investigate any instances of such activity, especially if found in conjunction with other suspicious behaviors or on systems that should not be using PowerShell for such tasks.
Windows PowerShell Process With Malicious String
The following analytic detects the execution of multiple offensive toolkits and commands through the process execution datamodel. This method captures commands given directly to powershell.exe, allowing for the identification of suspicious activities including several well-known tools used for credential theft, lateral movement, and persistence. If confirmed malicious, this could lead to unauthorized access, privilege escalation, and potential compromise of sensitive information within the environment.
Windows Powershell RemoteSigned File
The following analytic identifies the use of the "remotesigned" execution policy for PowerShell scripts. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions containing "remotesigned" and "-File". This activity is significant because the "remotesigned" policy allows locally created scripts to run without restrictions, posing a potential security risk. If confirmed malicious, an attacker could execute unauthorized scripts, leading to code execution, privilege escalation, or persistence within the environment.
Windows PowerShell ScheduleTask
The following analytic detects potential malicious activities involving PowerShell's task scheduling cmdlets. It leverages PowerShell Script Block Logging (EventCode 4104) to identify unusual or suspicious use of cmdlets like 'New-ScheduledTask' and 'Set-ScheduledTask'. This activity is significant as attackers often use these cmdlets for persistence and remote execution of malicious code. If confirmed malicious, this could allow attackers to maintain access, deliver additional payloads, or execute ransomware, leading to data theft or other severe impacts. Immediate investigation and mitigation are crucial to prevent further compromise.
Windows PowerShell Script Block With Malicious String
The following analytic detects the execution of multiple offensive toolkits and commands by leveraging PowerShell Script Block Logging (EventCode=4104). This method captures and logs the full command sent to PowerShell, allowing for the identification of suspicious activities including several well-known tools used for credential theft, lateral movement, and persistence. If confirmed malicious, this could lead to unauthorized access, privilege escalation, and potential compromise of sensitive information within the environment.
Windows PowerShell Script From WindowsApps Directory
The following analytic identifies the execution of PowerShell scripts from the WindowsApps directory, which is a common technique used in malicious MSIX package execution. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process command lines and parent process paths. This activity is significant as adversaries have been observed using MSIX packages with embedded PowerShell scripts (particularly StartingScriptWrapper.ps1) to execute malicious code. If confirmed malicious, this could allow attackers to execute arbitrary code, establish persistence, or deliver malware while evading traditional detection mechanisms.
Windows PowerShell WMI Win32 ScheduledJob
The following analytic detects the use of the Win32_ScheduledJob WMI class via PowerShell script block logging. This class, which manages scheduled tasks, is disabled by default due to security concerns and must be explicitly enabled through registry modifications. The detection leverages PowerShell event code 4104 and script block text analysis. Monitoring this activity is crucial as it may indicate malicious intent, especially if the class was enabled by an attacker. If confirmed malicious, this could allow attackers to persist in the environment by creating scheduled tasks.
Windows PowerSploit GPP Discovery
The following analytic detects the execution of the Get-GPPPassword PowerShell cmdlet, which is used to search for unsecured credentials in Group Policy Preferences (GPP). This detection leverages PowerShell Script Block Logging to identify specific script block text associated with this cmdlet. Monitoring this activity is crucial as it can indicate an attempt to retrieve and decrypt stored credentials from SYSVOL, potentially leading to unauthorized access. If confirmed malicious, this activity could allow an attacker to escalate privileges or move laterally within the network by exploiting exposed credentials.
Windows PowerView AD Access Control List Enumeration
The following analytic detects the execution of PowerView PowerShell cmdlets `Get-ObjectAcl` or `Get-DomainObjectAcl`, which are used to enumerate Access Control List (ACL) permissions for Active Directory objects. It leverages Event ID 4104 from PowerShell Script Block Logging to identify this activity. This behavior is significant as it may indicate an attempt to discover weak permissions in Active Directory, potentially leading to privilege escalation. If confirmed malicious, attackers could exploit these permissions to gain unauthorized access or escalate their privileges within the network.
Windows PowerView Constrained Delegation Discovery
The following analytic detects the use of PowerView commandlets to discover Windows endpoints with Kerberos Constrained Delegation. It leverages PowerShell Script Block Logging (EventCode=4104) to identify specific commandlets like `Get-DomainComputer` or `Get-NetComputer` with the `-TrustedToAuth` parameter. This activity is significant as it indicates potential reconnaissance efforts by adversaries or Red Teams to map out privileged delegation settings in Active Directory. If confirmed malicious, this could allow attackers to identify high-value targets for further exploitation, potentially leading to privilege escalation or lateral movement within the network.
Windows PowerView Kerberos Service Ticket Request
The following analytic detects the execution of the `Get-DomainSPNTicket` commandlet, part of the PowerView tool, by leveraging PowerShell Script Block Logging (EventCode=4104). This commandlet requests Kerberos service tickets for specified service principal names (SPNs). Monitoring this activity is crucial as it can indicate attempts to perform Kerberoasting, a technique used to extract SPN account passwords via cracking tools like hashcat. If confirmed malicious, this activity could allow attackers to gain unauthorized access to sensitive accounts, potentially leading to privilege escalation and further network compromise.
Windows PowerView SPN Discovery
The following analytic detects the execution of the `Get-DomainUser` or `Get-NetUser` PowerShell cmdlets with the `-SPN` parameter, indicating the use of PowerView for SPN discovery. It leverages PowerShell Script Block Logging (EventCode=4104) to identify these specific commands. This activity is significant as it suggests an attempt to enumerate domain accounts associated with Service Principal Names (SPNs), a common precursor to Kerberoasting attacks. If confirmed malicious, this could allow an attacker to identify and target accounts for credential theft, potentially leading to unauthorized access and privilege escalation within the network.
Windows PowerView Unconstrained Delegation Discovery
The following analytic detects the use of PowerView commandlets to discover Windows endpoints with Kerberos Unconstrained Delegation. It leverages PowerShell Script Block Logging (EventCode=4104) to identify specific commands like `Get-DomainComputer` or `Get-NetComputer` with the `-Unconstrained` parameter. This activity is significant as it indicates potential reconnaissance efforts by adversaries or Red Teams to map out privileged delegation settings in Active Directory. If confirmed malicious, this could allow attackers to identify high-value targets for further exploitation, potentially leading to privilege escalation or lateral movement within the network.
Windows Private Keys Discovery
The following analytic identifies processes that retrieve information related to private key files, often used by post-exploitation tools like winpeas. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions that search for private key certificates. This activity is significant as it indicates potential attempts to locate insecurely stored credentials, which adversaries can exploit for privilege escalation, persistence, or remote service authentication. If confirmed malicious, this behavior could allow attackers to access sensitive information, escalate privileges, or maintain persistence within the compromised environment.
Windows Privilege Escalation Suspicious Process Elevation
The following analytic detects when a process running with low or medium integrity from a user account spawns an elevated process with high or system integrity in suspicious locations. This behavior is identified using process execution data from Windows process monitoring. This activity is significant as it may indicate a threat actor successfully elevating privileges, which is a common tactic in advanced attacks. If confirmed malicious, this could allow the attacker to execute code with higher privileges, potentially leading to full system compromise and persistent access.
Windows Privilege Escalation System Process Without System Parent
The following analytic detects any system integrity level process spawned by a non-system account. It leverages Sysmon EventID 1, focusing on process integrity and parent user data. This behavior is significant as it often indicates successful privilege escalation to SYSTEM from a user-controlled process or service. If confirmed malicious, this activity could allow an attacker to gain full control over the system, execute arbitrary code, and potentially compromise the entire environment.
Windows Privilege Escalation User Process Spawn System Process
The following analytic detects when a process with low, medium, or high integrity spawns a system integrity process from a user-controlled location. This behavior is indicative of privilege escalation attempts where attackers elevate their privileges to SYSTEM level from a user-controlled process or service. The detection leverages Sysmon data, specifically Event ID 15, to identify such transitions. Monitoring this activity is crucial as it can signify an attacker gaining SYSTEM-level access, potentially leading to full control over the affected system, unauthorized access to sensitive data, and further malicious activities.
Windows Privileged Group Modification
This analytic detects modifications to privileged groups in Active Directory, including addition, creation, deletion, and changes to various types of groups such as local, global, universal, and LDAP query groups. It specifically monitors for changes to high-privilege groups like "Administrators", "Domain Admins", "Enterprise Admins", and "ESX Admins", among others. This detection is particularly relevant in the context of potential exploitation of vulnerabilities like the VMware ESXi Active Directory Integration Authentication Bypass (CVE-2024-37085), where attackers may attempt to manipulate privileged groups to gain unauthorized access to systems.
Windows Process Commandline Discovery
The following analytic detects the use of Windows Management Instrumentation Command-line (WMIC) to retrieve information about running processes, specifically targeting the command lines used to launch those processes. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on logs containing process details and command-line executions. This activity is significant as it may indicate suspicious behavior, such as a user or process gathering detailed process information, which is uncommon for non-technical users. If confirmed malicious, this could allow an attacker to gain insights into running processes, aiding in further exploitation or lateral movement.
Windows Process Executed From Removable Media
This analytic is used to identify when a removable media device is attached to a machine and then a process is executed from the same drive letter assigned to the removable media device. Adversaries and Insider Threats may use removable media devices for several malicious activities, including initial access, execution, and exfiltration.
Windows Process Execution From ProgramData
The following analytic identifies processes running from file paths within the ProgramData directory, a common location abused by adversaries for executing malicious code while evading detection. Threat actors often drop and execute payloads from this directory to bypass security controls, as it typically has write permissions for standard users. While this behavior can indicate malware execution or persistence techniques, it is important to note that some legitimate software, installers, and update mechanisms also run from ProgramData, leading to potential false positives. Security teams should validate detections by correlating with other indicators, such as unusual parent processes, unsigned binaries, or anomalous network activity.
Windows Process Execution From RDP Share
The following analytic identifies process executions originating from RDP shares on Windows endpoints. Remote Desktop Protocol (RDP) shares, typically accessed via the "tsclient" path, allow users to share files between their local machine and a remote desktop session. However, threat actors may exploit RDP shares to execute malicious processes or transfer harmful files onto a compromised system. This detection focuses on identifying any process executions that originate from RDP shares, which could indicate unauthorized access or malicious activity. Security teams should investigate any instances of such process executions, especially if they are found on systems that should not be using RDP shares or if the executed processes are unfamiliar or suspicious.
Windows Process Execution in Temp Dir
The following analytic identifies processes running from %temp% directory file paths. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific process paths within the Endpoint data model. This activity is significant because adversaries often use unconventional file paths to execute malicious code without requiring administrative privileges. If confirmed malicious, this behavior could indicate an attempt to bypass security controls, leading to unauthorized software execution, potential system compromise, and further malicious activities within the environment.
Windows Process Injection In Non-Service SearchIndexer
The following analytic identifies instances of the searchindexer.exe process that are not spawned by services.exe, indicating potential process injection. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and parent processes. This activity is significant because QakBot malware often uses a fake searchindexer.exe to evade detection and perform malicious actions such as data exfiltration and keystroke logging. If confirmed malicious, this activity could allow attackers to maintain persistence, steal sensitive information, and communicate with command and control servers.