Detection rules › Splunk

WSReset UAC Bypass

Author
Steven Dick, Teoderick Contreras, Splunk
Source
upstream

The following analytic detects a suspicious modification of the registry aimed at bypassing User Account Control (UAC) by leveraging WSReset.exe. It identifies the creation or modification of specific registry values under the path "\AppX82a6gwre4fdg3bt635tn5ctqjf8msdd2\Shell\open\command". This detection uses data from Endpoint Detection and Response (EDR) agents, focusing on process and registry events. This activity is significant because UAC bypass techniques can allow attackers to execute high-privilege actions without user consent. If confirmed malicious, this could lead to unauthorized code execution and potential system compromise.

MITRE ATT&CK coverage

TacticTechniques
Privilege EscalationT1548.002 Abuse Elevation Control Mechanism: Bypass User Account Control
Defense EvasionT1548.002 Abuse Elevation Control Mechanism: Bypass User Account Control

Event coverage

ProviderEvent IDTitle
Sysmon12RegistryEvent (Object create and delete)
Sysmon13RegistryEvent (Value Set)

Stages and Predicates

Stage 1: tstats

tstats WHERE (Registry.registry_value_name="(Default)" OR Registry.registry_value_name="DelegateExecute") Registry.registry_path="*\\AppX82a6gwre4fdg3bt635tn5ctqjf8msdd2\\Shell\\open\\command*" 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: search

search

Stage 4: search

search

Stage 5: 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
  • "*\\AppX82a6gwre4fdg3bt635tn5ctqjf8msdd2\\Shell\\open\\command*"
Registry.registry_value_nameeq
  • "(Default)" corpus 2 (splunk 2)
  • "DelegateExecute"