Auto Admin Logon Registry Entry: endpointEndpointNoneversion:15
The following analytic detects a suspicious registry modification that enables auto admin logon on a host. It leverages data from the Endpoint.Registry data model, specifically looking for changes to the "AutoAdminLogon" value within the "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon" registry path. This activity is significant because it was observed in BlackMatter ransomware attacks to maintain access after a safe mode reboot, facilitating further encryption. If confirmed malicious, this could allow attackers to automatically log in and continue their operations, potentially leading to widespread network encryption and data loss.
Known Services Killed by Ransomware: endpointEndpoint2025-02-07version:8
This analytic has been deprecated in favor of a new analytic - Windows Security And Backup Services Stop. The following analytic detects the suspicious termination of known services commonly targeted by ransomware before file encryption. It leverages Windows System Event Logs (EventCode 7036) to identify when critical services such as Volume Shadow Copy, backup, and antivirus services are stopped. This activity is significant because ransomware often disables these services to avoid errors and ensure successful file encryption. If confirmed malicious, this behavior could lead to widespread data encryption, rendering files inaccessible and potentially causing significant operational disruption and data loss.
Change To Safe Mode With Network Config: endpointEndpointNoneversion:12
The following analytic detects the execution of a suspicious `bcdedit` command that configures a host to boot in safe mode with network support. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions involving `bcdedit.exe` with specific parameters. This activity is significant because it is a known technique used by BlackMatter ransomware to force a compromised host into safe mode for continued encryption. If confirmed malicious, this could allow attackers to bypass certain security controls, persist in the environment, and continue their malicious activities.
SchCache Change By App Connect And Create ADSI Object: endpointEndpointNoneversion:11
The following analytic detects an application attempting to connect and create an ADSI object to perform an LDAP query. It leverages Sysmon EventCode 11 to identify changes in the Active Directory Schema cache files located in %LOCALAPPDATA%\Microsoft\Windows\SchCache or %systemroot%\SchCache. This activity is significant as it can indicate the presence of suspicious applications, such as ransomware, using ADSI object APIs for LDAP queries. If confirmed malicious, this behavior could allow attackers to gather sensitive directory information, potentially leading to further exploitation or lateral movement within the network.
Windows Security And Backup Services Stop: endpointEndpointNoneversion:8
The following analytic detects the suspicious termination of known services commonly targeted by ransomware before file encryption. It leverages Windows System Event Logs (EventCode 7036) to identify when critical services such as Volume Shadow Copy, backup, and antivirus services are stopped. This activity is significant because ransomware often disables these services to avoid errors and ensure successful file encryption. If confirmed malicious, this behavior could lead to widespread data encryption, rendering files inaccessible and potentially causing significant operational disruption and data loss.
Modification Of Wallpaper: endpointEndpointNoneversion:11
The following analytic detects the modification of registry keys related to the desktop wallpaper settings. It leverages Sysmon EventCode 13 to identify changes to the "Control Panel\\Desktop\\Wallpaper" and "Control Panel\\Desktop\\WallpaperStyle" registry keys, especially when the modifying process is not explorer.exe or involves suspicious file paths like temp or public directories. This activity is significant as it can indicate ransomware behavior, such as the REVIL ransomware, which changes the wallpaper to display a ransom note. If confirmed malicious, this could signify a compromised machine and the presence of ransomware, leading to potential data encryption and extortion.
Add DefaultUser And Password In Registry: endpointEndpointNoneversion:15
The following analytic detects suspicious registry modifications that implement auto admin logon by adding DefaultUserName and DefaultPassword values. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to the "SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon" registry path. This activity is significant because it is associated with BlackMatter ransomware, which uses this technique to automatically log on to compromised hosts and continue encryption after a safe mode boot. If confirmed malicious, this could allow attackers to maintain persistence and further encrypt the network, leading to significant data loss and operational disruption.
Bcdedit Command Back To Normal Mode Boot: endpointEndpointNoneversion:12
The following analytic detects the execution of a suspicious `bcdedit` command that reconfigures a host from safe mode back to normal boot. This detection leverages Endpoint Detection and Response (EDR) data, focusing on command-line executions involving `bcdedit.exe` with specific parameters. This activity is significant as it may indicate the presence of ransomware, such as BlackMatter, which manipulates boot configurations to facilitate encryption processes. If confirmed malicious, this behavior could allow attackers to maintain control over the boot process, potentially leading to further system compromise and data encryption.
Ransomware Notes bulk creation: endpointEndpointNoneversion:16
The following analytic identifies the bulk creation of ransomware notes (e.g., .txt, .html, .hta files) on an infected machine. It leverages Sysmon EventCode 11 to detect multiple instances of these file types being created within a short time frame. This activity is significant as it often indicates an active ransomware attack, where the attacker is notifying the victim of the encryption. If confirmed malicious, this behavior could lead to widespread data encryption, rendering critical files inaccessible and potentially causing significant operational disruption.
