Detection Strategy for Fileless Storage via Registry, WMI, and Shared Memory

Technique Detected:  Fileless Storage | T1027.011

ID: DET0344
Domains: Enterprise
Analytics: AN0973, AN0974
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN0973

Detects abuse of fileless storage mechanisms such as Registry keys, WMI classes, and Event Logs used to stage payloads, scripts, or encoded content outside traditional files.

Log Sources
Data Component Name Channel
Windows Registry Key Modification (DC0063) WinEventLog:Security EventCode=4657
WMI Creation (DC0008) WinEventLog:Application WMI Object Creation Events
Mutable Elements
Field Description
RegistryPathFilter Scoped to suspicious or abused paths like HKCU\Software\Classes\ or HKLM\SYSTEM\CurrentControlSet\Services\
PayloadEntropyThreshold Minimum entropy level to flag suspicious registry or WMI content as encoded payloads
TimeWindow Temporal window for correlating WMI/registry modifications with process creation or network usage

AN0974

Detects usage of shared memory directories (/dev/shm, /run/shm) for temporary storage of obfuscated, encoded, or executable data without persistence to disk.

Log Sources
Data Component Name Channel
File Creation (DC0039) auditd:SYSCALL open, write, unlink
File Metadata (DC0059) linux:osquery file_events.path
Mutable Elements
Field Description
PathPrefix Shared memory mount path used (e.g., /dev/shm/ or /run/shm/)
FilenameRegex Regex to match non-standard, suspicious, or encoded filenames
ExecCorrelationWindow Time window to correlate process execution from shared memory directories