Malicious ValleyRAT RuntimeBroker Masquerade in RunTime Directory

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects execution of RuntimeBroker.exe from C:\Program Files\RunTime, a masquerading location used by the Silver Fox APT to deploy its ValleyRAT loader. The legitimate RuntimeBroker.exe lives in System32, so a same-named binary under a RunTime folder is a trusted-name wrong-context indicator of the ValleyRAT dropper.

Reporting behind it

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Malicious ValleyRAT RuntimeBroker Masquerade in RunTime Directory

Pivot detection · T1036.005 · 9 related

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