EXPLORE DETECTIONS
Scheduled Task Creation on Remote Endpoint using At
The following analytic detects the creation of scheduled tasks on remote Windows endpoints using the at.exe command. This detection leverages Endpoint Detection and Response (EDR) telemetry, focusing on process creation events involving at.exe with remote command-line arguments. Identifying this activity is significant for a SOC as it may indicate lateral movement or remote code execution attempts by an attacker. If confirmed malicious, this activity could lead to unauthorized access, persistence, or execution of malicious code, potentially resulting in data theft or further compromise of the network.
Scheduled Task Deleted Or Created via CMD
The following analytic detects the creation or deletion of scheduled tasks via schtasks.exe when invoked with create or delete flags, specifically focusing on those executions where the process includes additional parameters such as /tr, /sc, or /ru. The detection uses Endpoint Detection and Response (EDR) telemetry mapped to the Endpoint data model, and filters out events originating from trusted system paths like C:\Windows\System32 or C:\Program Files. It further narrows results to cases where schtasks.exe is launched by potentially suspicious parent processes such as cmd.exe, wscript.exe, or cscript.exe, and excludes service accounts. This behavior may indicate adversary efforts to gain persistence or evade detection by manipulating scheduled tasks using scripts or command shells. If confirmed malicious, such activity could lead to unauthorized code execution or the removal of monitoring mechanisms on endpoints.
Scheduled Task Initiation on Remote Endpoint
The following analytic detects the use of 'schtasks.exe' to start a Scheduled Task on a remote endpoint. This detection leverages Endpoint Detection and Response (EDR) data, focusing on process details such as process name, parent process, and command-line executions. This activity is significant as adversaries often abuse Task Scheduler for lateral movement and remote code execution. If confirmed malicious, this behavior could allow attackers to execute arbitrary code remotely, potentially leading to further compromise of the network.
Schtasks Run Task On Demand
The following analytic detects the execution of a Windows Scheduled Task on demand via the shell or command line. It leverages process-related data, including process name, parent process, and command-line executions, sourced from endpoint logs. The detection focuses on 'schtasks.exe' with an associated 'run' command. This activity is significant as adversaries often use it to force the execution of their created Scheduled Tasks for persistent access or lateral movement within a compromised machine. If confirmed malicious, this could allow attackers to maintain persistence or move laterally within the network, potentially leading to further compromise.
Schtasks scheduling job on remote system
The following analytic detects the use of 'schtasks.exe' to create a scheduled task on a remote system, indicating potential lateral movement or remote code execution. It leverages process data from Endpoint Detection and Response (EDR) agents, focusing on specific command-line arguments and flags. This activity is significant as it may signify an adversary's attempt to persist or execute code remotely. If confirmed malicious, this could allow attackers to maintain access, execute arbitrary commands, or further infiltrate the network, posing a severe security risk.
Schtasks used for forcing a reboot
The following analytic detects the use of 'schtasks.exe' to schedule forced system reboots using the 'shutdown' and '/create' flags. It leverages endpoint process data to identify instances where these specific command-line arguments are used. This activity is significant because it may indicate an adversary attempting to disrupt operations or force a reboot to execute further malicious actions. If confirmed malicious, this could lead to system downtime, potential data loss, and provide an attacker with an opportunity to execute additional payloads or evade detection.
Screensaver Event Trigger Execution
The following analytic detects modifications to the SCRNSAVE.EXE registry entry, indicating potential event trigger execution via screensaver settings for persistence or privilege escalation. It leverages registry activity data from the Endpoint data model to identify changes to the specified registry path. This activity is significant as it is a known technique used by APT groups and malware to maintain persistence or escalate privileges. If confirmed malicious, this could allow an attacker to execute arbitrary code with elevated privileges, leading to further system compromise and persistent access.
Script Execution via WMI
The following analytic detects the execution of scripts via Windows Management Instrumentation (WMI) by monitoring the process 'scrcons.exe'. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events. WMI-based script execution is significant because adversaries often use it to perform malicious activities stealthily, such as system compromise, data exfiltration, or establishing persistence. If confirmed malicious, this activity could allow attackers to execute arbitrary code, escalate privileges, or maintain long-term access to the environment. Analysts should differentiate between legitimate administrative use and potential threats.
Sdclt UAC Bypass
The following analytic detects suspicious modifications to the sdclt.exe registry, a technique often used to bypass User Account Control (UAC). It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific registry paths and values associated with sdclt.exe. This activity is significant because UAC bypasses can allow attackers to execute payloads with elevated privileges without user consent. If confirmed malicious, this could lead to unauthorized code execution, privilege escalation, and potential persistence within the environment, posing a severe security risk.
Sdelete Application Execution
The following analytic detects the execution of the sdelete.exe application, a Sysinternals tool often used by adversaries to securely delete files and remove forensic evidence from a targeted host. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process execution logs. Monitoring this activity is crucial as sdelete.exe is not commonly used in regular operations and its presence may indicate an attempt to cover malicious activities. If confirmed malicious, this could lead to the loss of critical forensic data, hindering incident response and investigation efforts.
SearchProtocolHost with no Command Line with Network
The following analytic detects instances of searchprotocolhost.exe running without command line arguments but with an active network connection. This behavior is identified using Endpoint Detection and Response (EDR) telemetry, focusing on process execution and network traffic data. It is significant because searchprotocolhost.exe typically runs with specific command line arguments, and deviations from this norm can indicate malicious activity, such as Cobalt Strike usage. If confirmed malicious, this activity could allow attackers to establish network connections for command and control, potentially leading to data exfiltration or further system compromise.
SecretDumps Offline NTDS Dumping Tool
The following analytic detects the potential use of the secretsdump.py tool to dump NTLM hashes from a copy of ntds.dit and the SAM, SYSTEM, and SECURITY registry hives. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific command-line patterns and process names associated with secretsdump.py. This activity is significant because it indicates an attempt to extract sensitive credential information offline, which is a common post-exploitation technique. If confirmed malicious, this could allow an attacker to obtain NTLM hashes, facilitating further lateral movement and potential privilege escalation within the network.
ServicePrincipalNames Discovery with PowerShell
The following analytic detects the use of `powershell.exe` to query the domain for Service Principal Names (SPNs) using Script Block Logging EventCode 4104. It identifies the use of the KerberosRequestorSecurityToken class within the script block, which is equivalent to using setspn.exe. This activity is significant as it often precedes kerberoasting or silver ticket attacks, which can lead to credential theft. If confirmed malicious, attackers could leverage this information to escalate privileges or persist within the environment.
ServicePrincipalNames Discovery with SetSPN
The following analytic detects the use of `setspn.exe` to query the domain for Service Principal Names (SPNs). This detection leverages Endpoint Detection and Response (EDR) data, focusing on specific command-line arguments associated with `setspn.exe`. Monitoring this activity is crucial as it often precedes Kerberoasting or Silver Ticket attacks, which can lead to credential theft. If confirmed malicious, an attacker could use the gathered SPNs to escalate privileges or persist within the environment, posing a significant security risk.
Services Escalate Exe
The following analytic identifies the execution of a randomly named binary via `services.exe`, indicative of privilege escalation using Cobalt Strike's `svc-exe`. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process lineage and command-line executions. This activity is significant as it often follows initial access, allowing adversaries to escalate privileges and establish persistence. If confirmed malicious, this behavior could enable attackers to execute arbitrary code, maintain long-term access, and potentially move laterally within the network, posing a severe threat to the organization's security.
Services LOLBAS Execution Process Spawn
The following analytic identifies `services.exe` spawning a LOLBAS (Living Off the Land Binaries and Scripts) execution process. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where `services.exe` is the parent process. This activity is significant because adversaries often abuse the Service Control Manager to execute malicious code via native Windows binaries, facilitating lateral movement. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, escalate privileges, or maintain persistence within the environment, posing a severe security risk.
Set Default PowerShell Execution Policy To Unrestricted or Bypass
The following analytic detects changes to the PowerShell ExecutionPolicy in the registry to "Unrestricted" or "Bypass." It leverages data from Endpoint Detection and Response (EDR) agents, focusing on registry modifications under the path *Software\Microsoft\Powershell\1\ShellIds\Microsoft.PowerShell*. This activity is significant because setting the ExecutionPolicy to these values can allow the execution of potentially malicious scripts without restriction. If confirmed malicious, this could enable an attacker to execute arbitrary code, leading to further compromise of the system and potential escalation of privileges.
Shai-Hulud 2 Exfiltration Artifact Files
Detects creation of exfiltration artifact files associated with Shai-Hulud 2.0 npm supply chain malware. The malware creates cloud.json, contents.json, environment.json, truffleSecrets.json, and actionsSecrets.json files containing harvested credentials from AWS, Azure, GCP, GitHub secrets, and environment variables. These files are staged before being pushed to attacker-controlled repositories.
Shai-Hulud Workflow File Creation or Modification
Detects creation or deletion of malicious GitHub Actions workflow files associated with Shai-Hulud worm variants on Linux or Windows endpoints. This includes the original shai-hulud-workflow.yml, the 2.0 backdoor discussion.yaml (enables command injection via GitHub Discussions on self-hosted runners named SHA1HULUD), and the secrets exfiltration workflow formatter_*.yml pattern. These files are used to exfiltrate credentials and propagate across repositories.
Shim Database File Creation
The following analytic detects the creation of shim database files (.sdb) in default directories using the sdbinst.exe application. It leverages filesystem activity data from the Endpoint.Filesystem data model to identify file writes to the Windows\AppPatch\Custom directory. This activity is significant because shims can intercept and alter API calls, potentially allowing attackers to bypass security controls or execute malicious code. If confirmed malicious, this could lead to unauthorized code execution, privilege escalation, or persistent access within the environment.
Shim Database Installation With Suspicious Parameters
The following analytic detects the execution of sdbinst.exe with parameters indicative of silently creating a shim database. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line arguments. This activity is significant because shim databases can be used to intercept and manipulate API calls, potentially allowing attackers to bypass security controls or achieve persistence. If confirmed malicious, this could enable unauthorized code execution, privilege escalation, or persistent access to the compromised system.
Short Lived Scheduled Task
The following analytic detects the creation and deletion of scheduled tasks within a short time frame (less than 30 seconds) using Windows Security EventCodes 4698 and 4699. This behavior is identified by analyzing Windows Security Event Logs and leveraging the Windows TA for parsing. Such activity is significant as it may indicate lateral movement or remote code execution attempts by adversaries. If confirmed malicious, this could lead to unauthorized access, data exfiltration, or execution of malicious payloads, necessitating prompt investigation and response by security analysts.
Short Lived Windows Accounts
The following analytic detects the rapid creation and deletion of Windows accounts within a short time frame of 1 hour. It leverages the "Change" data model in Splunk, specifically monitoring events with result IDs 4720 (account creation) and 4726 (account deletion). This behavior is significant as it may indicate an attacker attempting to create and remove accounts quickly to evade detection or gain unauthorized access. If confirmed malicious, this activity could lead to unauthorized access, privilege escalation, or further malicious actions within the environment. Immediate investigation of flagged events is crucial to mitigate potential damage.
SilentCleanup UAC Bypass
The following analytic detects suspicious modifications to the registry that may indicate a UAC (User Account Control) bypass attempt via the SilentCleanup task. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on registry changes in the path "*\\Environment\\windir" with executable values. This activity is significant as it can allow an attacker to gain high-privilege execution without user consent, bypassing UAC protections. If confirmed malicious, this could lead to unauthorized administrative access, enabling further system compromise and persistence.