Malicious mshta Inline JavaScript GetObject Scriptlet Execution

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1218.005Mshta
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects mshta executing an inline javascript scriptlet that pulls a remote script object which is the LOLBIN execution primitive used in the Cobalt Kitty chain described by WithSecure. This technique proxies execution of an attacker hosted scriptlet through a trusted signed binary to evade application controls and fetch a second stage.

Reporting behind it

Related detections9 linkedT1218.005 — drag to rearrange

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Malicious Remote HTA Download and Execution via mshta by UAC-0050 (via process_creation)

Malicious Metasploit Stager Delivery via mshta Remote HTA (via process_creation)

Malicious mshta Launching WScript VBScript Loader

Suspicious Kimsuky Remote HTA Payload Execution via mshta (via process_creation)

Malicious mshta Inline JavaScript GetObject Scriptlet Execution

Pivot detection · T1218.005 · 9 related

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