Suspicious Sisfader RAT Loader DLL Written to Local AppData

ATT&CK techniques

Persistence → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1543.003Windows Service
Priv Esc
- T1543.003Windows Service
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects creation of a DLL named to appear as a helper component in the user Local AppData directory which the Sisfader RAT drops as its loader. Observed in NCC Group research on CVE-2017-8570 RTF documents delivering the Sisfader RAT. A helper-named DLL staged in a user profile directory is an indicator of masqueraded malware persistence.

Reporting behind it

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Suspicious Sisfader RAT Loader DLL Written to Local AppData

Pivot detection · T1543.003 · 9 related

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