Detect Mshta in Microsoft Sentinel
Adversaries may abuse mshta.exe to proxy execution of malicious .hta files and Javascript or VBScript through a trusted Windows utility. Mshta.exe executes Microsoft HTML Applications (HTA) files outside of the Internet Explorer browser security context, bypassing browser security settings and application control solutions. HTA files can be loaded locally, from remote URLs (mshta http://server/payload.hta), or as inline scripts (mshta vbscript:...). This technique is widely used by nation-state APTs including FIN7, Lazarus Group, APT29, APT32, MuddyWater, Kimsuky, Sidewinder, Gamaredon, and many others, making it one of the most commonly abused LOLBins for initial access and execution.
MITRE ATT&CK
- Tactic
- Defense Evasion
- Technique
- T1218 System Binary Proxy Execution
- Sub-technique
- T1218.005 Mshta
- Canonical reference
- https://attack.mitre.org/techniques/T1218/005/
KQL Detection Query
let SuspiciousPatterns = dynamic([
"http://", "https://", "vbscript:", "javascript:",
"GetObject", "WScript.Shell", "Shell.Application",
"CreateObject", "ActiveXObject", "cmd.exe", "powershell"
]);
DeviceProcessEvents
| where Timestamp > ago(24h)
| where FileName =~ "mshta.exe"
| extend RemoteURL = ProcessCommandLine has_any ("http://", "https://")
| extend InlineScript = ProcessCommandLine has_any ("vbscript:", "javascript:")
| extend GetObject = ProcessCommandLine has "GetObject"
| extend ShellInvoke = ProcessCommandLine has_any ("WScript.Shell", "Shell.Application", "CreateObject")
| extend SuspiciousParent = InitiatingProcessFileName has_any ("winword.exe", "excel.exe", "outlook.exe", "powerpnt.exe", "explorer.exe")
| extend HTAPath = ProcessCommandLine has_any ("Temp", "AppData", "Downloads", "Desktop", "Public")
| project Timestamp, DeviceName, AccountName, ProcessCommandLine, InitiatingProcessFileName,
InitiatingProcessCommandLine, RemoteURL, InlineScript, GetObject, ShellInvoke, SuspiciousParent, HTAPath
| sort by Timestamp desc
union (
DeviceProcessEvents
| where Timestamp > ago(24h)
| where InitiatingProcessFileName =~ "mshta.exe"
| project Timestamp, DeviceName, AccountName, FileName, ProcessCommandLine,
InitiatingProcessFileName, InitiatingProcessCommandLine
| sort by Timestamp desc
)Detects mshta.exe abuse across multiple attack patterns: remote HTA loading via HTTP/HTTPS (direct URL execution), inline VBScript/JavaScript execution, object creation patterns (WScript.Shell, CreateObject, GetObject) used for command execution, HTA files from suspicious paths, and mshta spawning child processes. The union catches downstream process creation.
Data Sources
Required Tables
False Positives & Tuning
- Legacy enterprise applications that use HTA files for management interfaces or configuration wizards
- Some older IT management tools (HP, Dell BIOS update utilities) that use HTA for their installation UI
- Legitimate corporate HTA-based tools deployed by IT for specific administrative tasks
- Software vendors whose legacy applications use HTA for splash screens or update notifications
Other platforms for T1218.005
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Mshta Remote HTA Execution
Expected signal: Sysmon Event ID 1: mshta.exe with URL in command line. Sysmon Event ID 3: Network connection attempt to 127.0.0.1:8080. Sysmon Event ID 22 (DNS Query) if a domain was used instead of IP. Security Event ID 4688.
- Test 2Mshta Inline VBScript Execution
Expected signal: Sysmon Event ID 1: mshta.exe with 'vbscript:' and 'CreateObject' in command line. Sysmon Event ID 1: cmd.exe as a child of mshta.exe. Sysmon Event ID 11: File created at temp path. Security Event ID 4688 for both processes.
- Test 3Mshta Launched from Office Application Path
Expected signal: Sysmon Event ID 1: cmd.exe, then mshta.exe with vbscript: and Execute in command line. InlineScript, GetObject/ShellInvoke indicators fire. If the obfuscated CreateObject resolves, WScript.Shell child process spawns calc.exe as grandchild of mshta.
References (7)
- https://attack.mitre.org/techniques/T1218/005/
- https://lolbas-project.github.io/lolbas/Binaries/Mshta/
- https://www.redcanary.com/blog/microsoft-html-application-hta-abuse-part-deux/
- https://www.fireeye.com/blog/threat-research/2017/04/fin7-phishing-lnk.html
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1218.005/T1218.005.md
- https://www.fireeye.com/blog/threat-research/2017/04/cve-2017-0199-hta-handler.html
- https://msdn.microsoft.com/library/ms536471.aspx
Unlock Pro Content
Get the full detection package for T1218.005 including response playbook, investigation guide, and atomic red team tests.