Detect Regsvr32 Application Control Bypass: endpointEndpointNoneversion:15
The following analytic identifies the abuse of Regsvr32.exe to proxy execution of malicious code, specifically detecting the loading of "scrobj.dll" by Regsvr32.exe. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events and command-line executions. This activity is significant because Regsvr32.exe is a trusted, signed Microsoft binary, often used in "Squiblydoo" attacks to bypass application control mechanisms. If confirmed malicious, this technique could allow an attacker to execute arbitrary code, potentially leading to system compromise and persistent access.
W3WP Spawning Shell: endpointEndpoint2025-10-16version:11
The following analytic identifies instances where a shell (PowerShell.exe or Cmd.exe) is spawned from W3WP.exe, the IIS worker process. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where the parent process is W3WP.exe. This activity is significant as it may indicate webshell activity, often associated with exploitation attempts like those by the HAFNIUM Group on Exchange servers. If confirmed malicious, this behavior could allow attackers to execute arbitrary commands, potentially leading to system compromise, data exfiltration, or further lateral movement within the network.
PowerShell WebRequest Using Memory Stream: endpointEndpointNoneversion:11
The following analytic detects the use of .NET classes in PowerShell to download a URL payload directly into memory, a common fileless malware staging technique. It leverages PowerShell Script Block Logging (EventCode=4104) to identify suspicious PowerShell commands involving `system.net.webclient`, `system.net.webrequest`, and `IO.MemoryStream`. This activity is significant as it indicates potential fileless malware execution, which is harder to detect and can bypass traditional file-based defenses. If confirmed malicious, this technique could allow attackers to execute code in memory, evade detection, and maintain persistence in the environment.
Any Powershell DownloadFile: endpointEndpoint2025-06-23version:16
The following analytic detects the use of PowerShell's `DownloadFile` method to download files. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs. This activity is significant as it is commonly used in malicious frameworks to download and execute additional payloads. If confirmed malicious, this could lead to unauthorized code execution, data exfiltration, or further compromise of the system. Analysts should investigate the source and destination of the download and review AMSI or PowerShell transaction logs for additional context.
Any Powershell DownloadString: endpointEndpoint2025-07-29version:14
The following analytic detects the use of PowerShell's `DownloadString` method to download files. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs that include command-line details. This activity is significant because `DownloadString` is commonly used in malicious PowerShell scripts to fetch and execute remote code. If confirmed malicious, this behavior could allow an attacker to download and run arbitrary code, potentially leading to unauthorized access, data exfiltration, or further compromise of the affected system.
Windows File Download Via PowerShell: endpointEndpointNoneversion:10
The following analytic detects the use of PowerShell's download methods such as
"DownloadString" and "DownloadData" from the WebClient class or Invoke-WebRequest
and it's aliases "IWR" or "Curl".
It leverages data from Endpoint Detection and Response (EDR) agents, focusing on
process execution logs that include command-line details.
This activity can be significant such methods and functions are commonly used in malicious
PowerShell scripts to fetch and execute remote code.
If confirmed malicious, this behavior could allow an attacker to download and run
arbitrary code, potentially leading to unauthorized access, data exfiltration,
or further compromise of the affected system.
System User Discovery With Whoami: endpointEndpointNoneversion:12
The following analytic detects the execution of `whoami.exe` without any arguments. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs. This activity is significant because both Red Teams and adversaries use `whoami.exe` to identify the current logged-in user, aiding in situational awareness and Active Directory discovery. If confirmed malicious, this behavior could indicate an attacker is gathering information to further compromise the system, potentially leading to privilege escalation or lateral movement within the network.
Web or Application Server Spawning a Shell: endpointEndpointNoneversion:5
The following analytic detects instances where Java, or Tomcat
processes spawn a Linux shell, which may indicate exploitation attempts, such as
those related to CVE-2021-44228 (Log4Shell). This detection leverages Endpoint Detection
and Response (EDR) telemetry, focusing on process names and parent-child process
relationships. This activity is significant as it can signify a compromised Java
application, potentially leading to unauthorized shell access. If confirmed malicious,
attackers could execute arbitrary commands, escalate privileges, or maintain persistent
access, posing a severe threat to the environment.
Attacker Tools On Endpoint: endpointEndpointNoneversion:19
The following analytic detects the execution of tools commonly exploited by cybercriminals, such as those used for unauthorized access, network scanning, privilege escalation, password dumping or data exfiltration.
It leverages process activity data from Endpoint Detection and Response (EDR) agents, focusing on known attacker tool names.
This activity is significant because it serves as an early warning system for potential security incidents, enabling prompt response. If confirmed malicious, this activity could lead to unauthorized access, data theft, or further network compromise, posing a severe threat to the organization's security infrastructure.
Windows Process Writing File to World Writable Path: endpointEndpointNoneversion:9
The following analytic identifies a process writing a .txt file to a world writable path. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on file creation events within specific directories. This activity is significant as adversaries often use such techniques to deliver payloads to a system, which is uncommon for legitimate processes. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, escalate privileges, or maintain persistence within the environment, posing a significant security risk.
PowerShell 4104 Hunting: endpointEndpointNoneversion:29
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.
