Detection rules › Splunk

Windows Modify Registry ProxyServer

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects modifications to the Windows registry key for setting up a proxy server. It leverages data from the Endpoint.Registry datamodel, focusing on changes to the "Internet Settings\ProxyServer" registry path. This activity is significant as it can indicate malware or adversaries configuring a proxy to facilitate unauthorized communication with Command and Control (C2) servers. If confirmed malicious, this could allow attackers to establish persistent, covert channels for data exfiltration or further exploitation of the compromised host.

MITRE ATT&CK coverage

TacticTechniques
PersistenceT1112 Modify Registry
Defense EvasionT1112 Modify Registry

Event coverage

ProviderEvent IDTitle
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE Registry.registry_path="*\\Internet Settings\\ProxyServer" BY Registry.action, Registry.dest, Registry.process_guid, Registry.process_id, Registry.registry_hive, Registry.registry_path, Registry.registry_key_name, Registry.registry_value_data, Registry.registry_value_name, Registry.registry_value_type, Registry.status, Registry.user, Registry.vendor_product

Stage 2: search

search

Stage 3: where

where isnotnull(registry_value_data)

Stage 4: search

search

Stage 5: search

search

Stage 6: 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_patheq
  • "*\\Internet Settings\\ProxyServer"