Windows Exfiltration Over C2 Via Invoke RestMethod: endpointEndpointNoneversion:14
The following analytic detects potential data exfiltration using PowerShell's Invoke-RestMethod. It leverages PowerShell Script Block Logging to identify scripts that attempt to upload files via HTTP POST requests. This activity is significant as it may indicate an attacker is exfiltrating sensitive data, such as desktop screenshots or files, to an external command and control (C2) server. If confirmed malicious, this could lead to data breaches, loss of sensitive information, and further compromise of the affected systems. Immediate investigation is recommended to determine the intent and scope of the activity.
Windows Suspicious Child Process Spawned From WebServer: endpointEndpointNoneversion:12
The following analytic identifies the execution of suspicious processes typically associated with WebShell activity on web servers. It detects when processes like `cmd.exe`, `powershell.exe`, or `bash.exe` are spawned by web server processes such as `w3wp.exe` or `nginx.exe`. This behavior is significant as it may indicate an adversary exploiting a web application vulnerability to install a WebShell, providing persistent access and command execution capabilities. If confirmed malicious, this activity could allow attackers to maintain control over the compromised server, execute arbitrary commands, and potentially escalate privileges or exfiltrate sensitive data.
Windows Curl Upload to Remote Destination: endpointEndpointNoneversion:18
The following analytic detects the use of Windows Curl.exe to upload a file to a remote destination.
It identifies command-line arguments such as `-T`, `--upload-file`, `-d`, `--data`, and `-F` in process execution logs.
This activity is significant because adversaries may use Curl to exfiltrate data or upload malicious payloads. If confirmed malicious, this could lead to data breaches or further compromise of the system.
Analysts should review parallel processes and network logs to determine if the upload was successful and isolate the endpoint if necessary.
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.
Windows WSUS Spawning Shell: endpointEndpointNoneversion:5
The following analytic identifies instances where a shell (PowerShell.exe or Cmd.exe) is spawned from wsusservice.exe, the Windows Server Update Services process. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where the parent process is wsusservice.exe. This activity is significant as it may indicate exploitation of CVE-2025-59287, a critical deserialization vulnerability in WSUS that allows unauthenticated remote code execution. If confirmed malicious, this behavior could allow attackers to execute arbitrary commands on WSUS servers, potentially leading to system compromise, data exfiltration, domain enumeration, or further lateral movement within the network.
Powershell Fileless Script Contains Base64 Encoded Content: endpointEndpointNoneversion:22
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.
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.
WinRM Spawning a Process: endpointEndpointNoneversion:11
The following analytic detects suspicious processes spawned by WinRM (wsmprovhost.exe). It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific child processes like cmd.exe, powershell.exe, and others. This activity is significant as it may indicate exploitation attempts of vulnerabilities like CVE-2021-31166, which could lead to system instability or compromise. If confirmed malicious, attackers could execute arbitrary commands, escalate privileges, or maintain persistence, posing a severe threat to the environment.
Malicious PowerShell Process - Encoded Command: endpointEndpointNoneversion:21
The following analytic detects the use of the EncodedCommand parameter in PowerShell processes.
It leverages Endpoint Detection and Response (EDR) data to identify variations of the EncodedCommand parameter, including shortened forms and different command switch types.
This activity can be significant because adversaries often use encoded commands to obfuscate malicious scripts, making detection harder.
If confirmed malicious, this behavior could allow attackers to execute hidden code, potentially leading to unauthorized access, privilege escalation, or persistent threats within the environment.
Review parallel events to determine legitimacy and tune based on known administrative scripts.
Windows Group Discovery Via Net: endpointEndpointNoneversion:7
The following analytic identifies the execution of `net.exe` with command-line arguments used to query global, local and domain groups. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant as it indicates potential reconnaissance efforts by adversaries to enumerate local or domain groups, which is a common step in Active Directory or privileged accounts discovery. If confirmed malicious, this behavior could allow attackers to gain insights into the domain structure, aiding in further attacks such as privilege escalation or lateral movement.
Possible Lateral Movement PowerShell Spawn: endpointEndpointNoneversion:17
The following analytic detects the spawning of a PowerShell process as a child or grandchild of commonly abused processes like services.exe, wmiprvse.exe, svchost.exe, wsmprovhost.exe, and mmc.exe.
It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and parent process names, as well as command-line executions.
This activity is significant as it could indicates lateral movement or remote code execution attempts by adversaries.
If confirmed malicious, this behavior could allow attackers to execute code remotely, escalate privileges, or persist within the environment.
Cisco NVM - Curl Execution With Insecure Flags: endpointEndpointNoneversion:8
This analytic detects the use of `curl.exe` with insecure flags such as `-k`, `--insecure`, `--proxy-insecure`, or `--doh-insecure`
which disable TLS certificate validation.
It leverages Cisco Network Visibility Module (NVM) flow data and process arguments
to identify outbound connections initiated by curl where TLS checks were explicitly disabled.
This behavior may indicate an attempt to bypass certificate validation to connect to potentially untrusted or malicious endpoints,
a common tactic in red team operations, malware staging, or data exfiltration over HTTPS.
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.
Windows Sensitive Group Discovery With Net: endpointEndpointNoneversion:9
The following analytic detects the execution of `net.exe` with command-line arguments used to query elevated domain or sensitive groups. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant as it indicates potential reconnaissance efforts by adversaries to identify high-privileged users within Active Directory. If confirmed malicious, this behavior could lead to further attacks aimed at compromising privileged accounts, escalating privileges, or gaining unauthorized access to sensitive systems and data.
PowerShell Domain Enumeration: endpointEndpointNoneversion:16
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.
Windows Common Abused Cmd Shell Risk Behavior: endpointEndpointNoneversion:10
The following analytic identifies instances where four or more distinct detection analytics are associated with malicious command line behavior on a specific host. This detection leverages the Command Line Interface (CLI) data from various sources to identify suspicious activities. This behavior is significant as it often indicates attempts to execute malicious commands, access sensitive data, install backdoors, or perform other nefarious actions. If confirmed malicious, attackers could gain unauthorized control, exfiltrate information, escalate privileges, or launch further attacks within the network, leading to severe compromise.
