EXPLORE DETECTIONS
Windows Drivers Loaded by Signature
The following analytic identifies all drivers being loaded on Windows systems using Sysmon EventCode 6 (Driver Load). It leverages fields such as driver path, signature status, and hash to detect potentially suspicious drivers. This activity is significant for a SOC as malicious drivers can be used to gain kernel-level access, bypass security controls, or persist in the environment. If confirmed malicious, this activity could allow an attacker to execute arbitrary code with high privileges, leading to severe system compromise and potential data exfiltration.
Windows EDRSilencer Custom Outbound Filter Added
The following analytic detects the EDRSilencer-specific Windows Filtering Platform filter name "Custom Outbound Filter" when it is configured with a block action. EDRSilencer creates WFP filters to block outbound traffic from EDR and security agent processes, impairing endpoint telemetry without requiring the tool binary to keep its original process name. EventCode 5447 identifies creation of the runtime filter with ChangeType %%16384, while EventCode 5441 can show the same persistent filter when the Base Filtering Engine starts.
Windows EDRSilencer Execution
Detects the usage of EDRSilencer. Inspired by the closed-source FireBlock tool from MdSec NightHawk, this custom tool was developed to block outbound traffic of running Endpoint Detection and Response (EDR) processes using Windows Filtering Platform (WFP) APIs. Its features include searching for running EDR processes and applying WFP filters to block outbound traffic, adding filters for specific processes, and removing filters either individually or globally. The tool includes a custom implementation to avoid file handle access issues with EDR processes by bypassing the CreateFileW API. It supports a wide range of EDRs, including Microsoft Defender, Carbon Black, SentinelOne, and more, though further testing on various EDRs is recommended. The tool has been tested on Windows 10 and Windows Server 2016, and its usage involves simple commands for blocking or unblocking traffic.
Windows EFI Bootloader File Modification
Detects where a process writes to critical EFI bootloader files (bootmgfw.efi or bootx64.efi) within the \EFI\Boot\ directory. These files are responsible for initializing the Windows Boot Manager during system startup. Modification or replacement of these files is highly unusual in normal operations and may indicate an attempt to install a bootkit, persist malicious code at the firmware level, or otherwise tamper with the system boot process.
Windows EFI Volume Mount Attempt Via Mountvol
Detects attempts to mount the EFI volume. The EFI system partition (ESP) is a special partition on a data storage device (usually a hard disk drive or solid-state drive) that computers adhering to the UEFI (Unified Extensible Firmware Interface) specification use to store data necessary for the system to boot, such as bootloaders, device drivers, and system utilities. This is used with attacks such as PKFail to modify the system on boot.
Windows Enable PowerShell Web Access
The following analytic detects the enabling of PowerShell Web Access via PowerShell commands. It leverages PowerShell script block logging (EventCode 4104) to identify the execution of the `Install-WindowsFeature` cmdlet with the `WindowsPowerShellWebAccess` parameter. This activity is significant because enabling PowerShell Web Access can facilitate remote execution of PowerShell commands, potentially allowing an attacker to gain unauthorized access to systems and networks.
Windows Enable Win32 ScheduledJob via Registry
The following analytic detects the creation of a new DWORD value named "EnableAt" in the registry path "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\Configuration". This modification enables the use of the at.exe or wmi Win32_ScheduledJob commands to add scheduled tasks on a Windows endpoint. The detection leverages registry event data from the Endpoint datamodel. This activity is significant because it may indicate that an attacker is enabling the ability to schedule tasks, potentially to execute malicious code at specific times or intervals. If confirmed malicious, this could allow persistent code execution on the system.
Windows Entra User Management Via Azure CLI
This analytic detects the usage of the Azure CLI to interact with user accounts such as creating or deleting a user. Adversaries create new users so that their malicious activity does not interrupt the normal functions of the compromised users and can remain undetected. While legitimate administrative use is expected, anomalous execution patterns, unexpected users, or unusual parent processes should be treated as potential indicators of compromise and investigated promptly.
Windows Error Report Created in ReportQueue Manually
The following analytic detects a .wer file being written into the Windows Error Reporting ReportQueue directory by a process other than the standard error-reporting binaries. Windows Error Reporting normally populates ReportQueue only through werfault.exe, werfaultsecure.exe, or wermgr.exe following an actual application crash. In the ShieldBreak exploit, the attacker fabricates a .wer report directly and manually invokes the QueueReporting scheduled task, which causes wermgr.exe to process the report and load an attacker-planted phantom DLL at SYSTEM integrity. If confirmed malicious, this activity indicates preparation for a local privilege escalation attempt abusing Windows Error Reporting.
Windows ESX Admins Group Creation Security Event
This analytic detects creation, deletion, or modification of the "ESX Admins" group in Active Directory. These events may indicate attempts to exploit the VMware ESXi Active Directory Integration Authentication Bypass vulnerability (CVE-2024-37085).
Windows ESX Admins Group Creation via Net
This analytic detects attempts to create an "ESX Admins" group using the Windows net.exe or net1.exe commands. This activity may indicate an attempt to exploit the VMware ESXi Active Directory Integration Authentication Bypass vulnerability (CVE-2024-37085). Attackers can use this method to gain unauthorized access to ESXi hosts by recreating the "ESX Admins" group after its deletion from Active Directory.
Windows ESX Admins Group Creation via PowerShell
This analytic detects attempts to create an "ESX Admins" group using PowerShell commands. This activity may indicate an attempt to exploit the VMware ESXi Active Directory Integration Authentication Bypass vulnerability (CVE-2024-37085). Attackers can use this method to gain unauthorized access to ESXi hosts by recreating the 'ESX Admins' group after its deletion from Active Directory.
Windows Event For Service Disabled
The following analytic detects when a Windows service is modified from a start type to disabled. It leverages system event logs, specifically EventCode 7040, to identify this change. This activity is significant because adversaries often disable security or other critical services to evade detection and maintain control over a compromised host. If confirmed malicious, this action could allow attackers to bypass security defenses, leading to further exploitation and persistence within the environment.
Windows Event Log Cleared
The following analytic detects the clearing of Windows event logs by identifying Windows Security Event ID 1102 or System log event 104. This detection leverages Windows event logs to monitor for log clearing activities. Such behavior is significant as it may indicate an attempt to cover tracks after malicious activities. If confirmed malicious, this action could hinder forensic investigations and allow attackers to persist undetected, making it crucial to investigate further and correlate with other alerts and data sources.
Windows Event Logging Service Has Shutdown
The following analytic detects the shutdown of the Windows Event Log service by leveraging Windows Event ID 1100. This event is logged every time the service stops, including during normal system shutdowns. Monitoring this activity is crucial as it can indicate attempts to cover tracks or disable logging. If confirmed malicious, an attacker could hide their activities, making it difficult to trace their actions and investigate further incidents. Analysts should verify if the shutdown was planned and review other alerts and data sources for additional suspicious behavior.
Windows Event Triggered Image File Execution Options Injection
The following analytic identifies the creation or modification of Image File Execution Options (IFEO) registry keys, detected via EventCode 3000 in the Application channel. This detection leverages Windows Event Logs to monitor for process names added to IFEO under specific registry paths. This activity is significant as it can indicate attempts to set traps for process monitoring or debugging, often used by attackers for persistence or evasion. If confirmed malicious, this could allow an attacker to execute arbitrary code or manipulate process behavior, leading to potential system compromise.
Windows Eventlog Cleared Via Wevtutil
The following analytic detects the usage of wevtutil.exe with the "clear-log" parameter in order to clear the contents of logs. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because clearing event logs can be an attempt to cover tracks after malicious actions, hindering forensic investigations. If confirmed malicious, this behavior could allow an attacker to erase evidence of their activities, making it difficult to trace their actions and understand the full scope of the compromise.
Windows EventLog Recon Activity Using Log Query Utilities
This analytic detects EventLog reconnaissance activity using utilities such as `wevtutil.exe`, `wmic.exe`, PowerShell cmdlets like `Get-WinEvent`, or WMI queries targeting `Win32_NTLogEvent`. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. These tools are often used by adversaries to extract usernames, IP addresses, session data, and event information for credential access or situational awareness during lateral movement. While these utilities are legitimate, execution with specific arguments or targeting sensitive logs like `Security`, `PowerShell`, or specific EventIDs (e.g., 4624, 4778) can indicate malicious intent. If confirmed malicious, this behavior could allow an attacker to extract sensitive info and potentially have leveraged access or move laterally.
Windows Excel Spawning Microsoft Project Application
The following analytic identifies the execution of uncommon Microsoft application executables as child processes of Microsoft Excel. Under normal conditions, Excel primarily spawns internal Office-related processes, and the creation of executables such as WINPROJ.EXE, FOXPROW.exe, or SCHDPLUS.exe is uncommon in typical business workflows. Adversaries may abuse this behavior to blend malicious activity within trusted applications, execute unauthorized code, or bypass application control mechanisms. This technique aligns with common tradecraft where Office applications are leveraged as initial access or execution vectors due to their prevalence in enterprise environments. Detecting this relationship helps defenders spot suspicious child processes that may indicate malware execution, persistence mechanisms, or attempts to establish command-and-control. Security teams should investigate the parent Excel process, the context of the ActivateMicrosoftApp() execution, and any subsequent network or file activity. While certain legitimate Office features could trigger this process in specific environments, its occurrence generally warrants further scrutiny to validate intent and rule out compromise.
Windows Excessive Disabled Services Event
The following analytic identifies an excessive number of system events where services are modified from start to disabled. It leverages Windows Event Logs (EventCode 7040) to detect multiple service state changes on a single host. This activity is significant as it may indicate an adversary attempting to disable security applications or other critical services, potentially leading to defense evasion or destructive actions. If confirmed malicious, this behavior could allow attackers to disable security defenses, disrupt system operations, and achieve their objectives on the compromised system.
Windows Excessive Service Stop Attempt
The following analytic detects multiple attempts to stop or delete services on a system using `net.exe` or `sc.exe`. It leverages Endpoint Detection and Response (EDR) telemetry, focusing on process names and command-line executions within a one-minute window. This activity is significant as it may indicate an adversary attempting to disable security or critical services to evade detection and further their objectives. If confirmed malicious, this could lead to the attacker gaining persistence, escalating privileges, or disrupting essential services, thereby compromising the system's security posture.
Windows Excessive Usage Of Net App
The following analytic detects excessive usage of `net.exe` within a one-minute interval. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, parent processes, and command-line executions. This behavior is significant as it may indicate an adversary attempting to create, delete, or disable multiple user accounts rapidly, a tactic observed in Monero mining incidents. If confirmed malicious, this activity could lead to unauthorized user account manipulation, potentially compromising system integrity and enabling further malicious actions.
Windows Exchange Autodiscover SSRF Abuse
This analytic identifies potential exploitation attempts of ProxyShell (CVE-2021-34473, CVE-2021-34523, CVE-2021-31207) and ProxyNotShell (CVE-2022-41040, CVE-2022-41082) vulnerabilities in Microsoft Exchange Server. The detection focuses on identifying the SSRF attack patterns used in these exploit chains. The analytic monitors for suspicious POST requests to /autodiscover/autodiscover.json endpoints that may indicate attempts to enumerate LegacyDN attributes as part of initial reconnaissance. It also detects requests containing X-Rps-CAT parameters that could indicate attempts to impersonate Exchange users and access the PowerShell backend. Additionally, it looks for MAPI requests that may be used to obtain user SIDs, along with suspicious user agents (particularly Python-based) commonly used in automated exploit attempts. If successful, these attacks can lead to remote code execution as SYSTEM, allowing attackers to deploy webshells, access mailboxes, or gain persistent access to the Exchange server and potentially the broader network environment.
Windows Executable in Loaded Modules
The following analytic identifies instances where executable files (.exe) are loaded as modules, detected through 'ImageLoaded' events in Sysmon logs. This method leverages Sysmon EventCode 7 to track unusual module loading behavior, which is significant as it deviates from the norm of loading .dll files. This activity is crucial for SOC monitoring because it can indicate the presence of malware like NjRAT, which uses this technique to load malicious modules. If confirmed malicious, this behavior could allow attackers to execute arbitrary code, maintain persistence, and further compromise the host system.