Malicious Fileless Execution via memfd Anonymous File on Linux Cloud Workload (via process_creation)

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.006Python
Persistence
Priv Esc
Defense Evasion
- T1620Reflective Code Loading
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a process whose executable path resolves to an in-memory memfd anonymous file, the fileless technique the PyLoose cryptomining attack used to run its XMRig payload from a Jupyter Notebook without touching disk. Attackers rely on memfd_create to evade file-based detection, so a process backed by a memfd descriptor on a cloud workload is highly suspicious.

Reporting behind it

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Malicious Fileless Execution via memfd Anonymous File on Linux Cloud Workload (via process_creation)

Pivot detection · T1059.006 · 9 related

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