Detection rules › Splunk

Windows Registry Payload Injection

Author
Steven Dick
Source
upstream

The following analytic detects suspiciously long data written to the Windows registry, a behavior often linked to fileless malware or persistence techniques. It leverages Endpoint Detection and Response (EDR) telemetry, focusing on registry events with data lengths exceeding 512 characters. This activity is significant as it can indicate an attempt to evade traditional file-based defenses, making it crucial for SOC monitoring. If confirmed malicious, this technique could allow attackers to maintain persistence, execute code, or manipulate system configurations without leaving a conventional file footprint.

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1027.011 Obfuscated Files or Information: Fileless Storage

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE Registry.registry_value_data="*" BY _time, Registry.dest, Registry.registry_path, Registry.registry_value_name, Registry.process_guid, Registry.registry_value_data, Registry.registry_key_name, Registry.registry_hive, Registry.status, Registry.action, Registry.process_id, Registry.user, Registry.vendor_product

Stage 2: search

search

Stage 3: eval

eval ... using (registry_value_data)

Stage 4: where

where reg_data_len>512

Stage 5: search

search

Stage 6: search

search

Stage 7: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Registry.registry_value_dataeq
  • *
reg_data_lengt
  • 512