Detect Regasm with Network Connection: endpointEndpointNoneversion:16
The following analytic detects the execution of regasm.exe establishing a network connection to a public IP address, excluding private IP ranges. This detection leverages Sysmon EventID 3 logs to identify such behavior. This activity is significant as regasm.exe is a legitimate Microsoft-signed binary that can be exploited to bypass application control mechanisms. If confirmed malicious, this behavior could indicate an adversary's attempt to establish a remote Command and Control (C2) channel, potentially leading to privilege escalation and further malicious actions within the environment.
Detect Regsvcs with No Command Line Arguments: endpointEndpointNoneversion:15
The following analytic detects instances of regsvcs.exe running without command line arguments. This behavior typically indicates process injection, where another process manipulates regsvcs.exe. The detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, IDs, and command-line executions. This activity is significant as it may signal an attempt to evade detection and execute malicious code. If confirmed malicious, the attacker could achieve code execution, potentially leading to privilege escalation, persistence, or access to sensitive information.
Detect Regasm Spawning a Process: endpointEndpointNoneversion:17
The following analytic detects regasm.exe spawning a child process. This behavior is identified using data from Endpoint Detection and Response (EDR) agents, focusing on process creation events where regasm.exe is the parent process. This activity is significant because regasm.exe spawning a process is rare and can indicate an attempt to bypass application control mechanisms. If confirmed malicious, this could allow an attacker to execute arbitrary code, potentially leading to privilege escalation or persistent access within the environment. Immediate investigation is recommended to determine the legitimacy of the spawned process and any associated activities.
Detect Regsvcs Spawning a Process: endpointEndpointNoneversion:15
The following analytic identifies regsvcs.exe spawning a child process. This behavior is detected using Endpoint Detection and Response (EDR) telemetry, focusing on process creation events where the parent process is regsvcs.exe. This activity is significant because regsvcs.exe rarely spawns child processes, and such behavior can indicate an attempt to bypass application control mechanisms. If confirmed malicious, this could allow an attacker to execute arbitrary code, potentially leading to privilege escalation or persistent access within the environment. Immediate investigation is recommended to determine the legitimacy of the spawned process and any associated suspicious activities.
Detect Regasm with no Command Line Arguments: endpointEndpointNoneversion:16
The following analytic detects instances of regasm.exe running without command line arguments. This behavior typically indicates process injection, where another process manipulates regasm.exe. The detection leverages Endpoint Detection and Response (EDR) data, focusing on process names and command-line executions. This activity is significant as it may signal an attempt to evade detection or execute malicious code. If confirmed malicious, attackers could achieve code execution, potentially leading to privilege escalation, persistence, or access to sensitive information. Investigate network connections, parallel processes, and suspicious module loads for further context.
Detect Regsvcs with Network Connection: endpointEndpointNoneversion:15
The following analytic identifies instances of Regsvcs.exe establishing a network connection to a public IP address, excluding private IP ranges. This detection leverages Sysmon EventID 3 logs to monitor network connections initiated by Regsvcs.exe. This activity is significant as Regsvcs.exe, a legitimate Microsoft-signed binary, can be exploited to bypass application control mechanisms and establish remote Command and Control (C2) channels. If confirmed malicious, this behavior could allow an attacker to escalate privileges, persist in the environment, and exfiltrate sensitive data. Immediate investigation and remediation are recommended.
