Analytics Story: NetSupport RMM Tool Abuse

Description

Detection analytics for the NetSupport Remote Manager Tool primarily focus on identifying its misuse, as it's a legitimate tool often leveraged by adversaries. Endpoint detection involves flagging the client32.exe executable running from unusual directories like Downloads or ProgramData instead of its standard Program Files location. Suspicious activity also encompasses renamed binaries with the internal name "client32" communicating with netsupportsoftware.com, or unauthenticated remote control sessions. Furthermore, monitoring for PowerShell execution associated with NetSupport Manager can reveal malicious deployment. These analytics help distinguish legitimate remote support from potential unauthorized access.

Why it matters

NetSupport Manager, a legitimate remote access tool, often finds itself weaponized by adversaries, transforming into a Remote Access Trojan (RAT) for covert access. The narrative of its detection begins by understanding this duality while IT teams use it for benign support, threat actors exploit its capabilities, often via phishing or fake updates, to gain unauthorized control. The tell-tale signs emerge when this legitimate tool operates outside its normal parameters. For instance, observing client32.exe running from unusual directories like Downloads or ProgramData, rather than its secure Program Files location, immediately raises a red flag. Similarly, the presence of clear-text HTTP traffic containing CMD=ENCD commands, instead of the expected secure HTTPS, signals malicious intent. Furthermore, renamed binaries still internally identifying as "client32" communicating with netsupportsoftware.com, or unauthenticated remote control sessions, paint a clear picture of abuse. These anomalies, coupled with suspicious PowerShell execution, allow detection analytics to differentiate legitimate remote assistance from a stealthy intrusion, enabling defenders to uncover the adversary's presence

Detections

Name ▲▼ Technique ▲▼ Type ▲▼
Registry Keys Used For Persistence Registry Run Keys / Startup Folder TTP
Windows Executable Masquerading as Benign File Types Masquerade File Type Anomaly
Windows Credentials from Password Stores Deletion Credentials from Password Stores TTP
Windows RunMRU Registry Key or Value Deleted Modify Registry Anomaly
Windows Scheduled Task with Highest Privileges Scheduled Task TTP
Windows RMM Tool Execution Remote Access Tools Anomaly
Domain Controller Discovery with Nltest Remote System Discovery TTP
Windows Cabinet File Extraction Via Expand Ingress Tool Transfer TTP
Windows Credentials from Password Stores Query Credentials from Password Stores Anomaly
Windows NetSupport RMM DLL Loaded By Uncommon Process Masquerading Anomaly
Allow Inbound Traffic In Firewall Rule Remote Desktop Protocol TTP
Windows Modify Registry to Add or Modify Firewall Rule Modify Registry Anomaly
Powershell Windows Defender Exclusion Commands Disable or Modify Tools TTP
Suspicious Scheduled Task from Public Directory Scheduled Task Anomaly
Add or Set Windows Defender Exclusion Disable or Modify Tools TTP
Windows PowerShell FakeCAPTCHA Clipboard Execution PowerShell, Windows Command Shell, Malicious Link TTP
Windows File and Directory Enable ReadOnly Permissions Windows Permissions TTP
LOLBAS With Network Traffic Ingress Tool Transfer, System Binary Proxy Execution, Exfiltration Over Web Service TTP
Windows Defender Exclusion Registry Entry Disable or Modify Tools TTP
Windows Firewall Rule Added Disable or Modify System Firewall Anomaly
Windows Firewall Rule Modification Disable or Modify System Firewall Anomaly
Windows File and Directory Permissions Enable Inheritance Windows Permissions Hunting
Windows File Download Via PowerShell PowerShell, Ingress Tool Transfer Anomaly
Scheduled Task Deleted Or Created via CMD Scheduled Task Anomaly
Ntdsutil Export NTDS NTDS TTP
Windows Credentials from Password Stores Creation Credentials from Password Stores TTP
Windows RDP Connection Successful RDP Hijacking Hunting
Detect MSHTA Url in Command Line Mshta TTP
ICACLS Grant Command File and Directory Permissions Modification Anomaly
Windows Firewall Rule Deletion Disable or Modify System Firewall Anomaly
System Information Discovery Detection System Information Discovery TTP
Windows Modify Registry Delete Firewall Rules Modify Registry TTP
Disable Windows Behavior Monitoring Disable or Modify Tools TTP
Powershell Fileless Script Contains Base64 Encoded Content Obfuscated Files or Information, PowerShell TTP

Data Sources

Name ▲▼ Platform ▲▼ Sourcetype ▲▼ Source ▲▼
Sysmon EventID 13 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Sysmon EventID 29 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Windows Event Log Security 4688 Windows icon Windows XmlWinEventLog XmlWinEventLog:Security
Sysmon EventID 1 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
CrowdStrike ProcessRollup2 Other crowdstrike:events:sensor crowdstrike
Sysmon EventID 12 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Sysmon EventID 7 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Powershell Script Block Logging 4104 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
Sysmon EventID 14 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Cisco Network Visibility Module Flow Data Network icon Network cisco:nvm:flowdata not_applicable
Sysmon EventID 3 Windows icon Windows XmlWinEventLog XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
Windows Event Log Security 4946 Windows icon Windows XmlWinEventLog XmlWinEventLog:Security
Windows Event Log Security 4947 Windows icon Windows XmlWinEventLog XmlWinEventLog:Security
Windows Event Log RemoteConnectionManager 1149 Windows icon Windows wineventlog WinEventLog:Microsoft-Windows-TerminalServices-RemoteConnectionManager/Operational
Windows Event Log Security 4948 Windows icon Windows XmlWinEventLog XmlWinEventLog:Security

References


Source: GitHub | Version: 2