Detection rules › Splunk

Windows Modify Registry UpdateServiceUrlAlternate

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects a suspicious modification to the Windows Update configuration registry key, specifically targeting the UpdateServiceUrlAlternate setting. It leverages data from the Endpoint.Registry datamodel to identify changes to this registry path. This activity is significant because adversaries, including malware like RedLine Stealer, exploit this technique to bypass detection and deploy additional payloads. If confirmed malicious, this modification could allow attackers to redirect update services, potentially leading to the execution of malicious code, further system compromise, and persistent evasion of security defenses.

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="*\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\UpdateServiceUrlAlternate" 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
  • "*\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\UpdateServiceUrlAlternate"