Detection rules › Splunk
Windows New EventLog ChannelAccess Registry Value Set
The following analytic detects suspicious modifications to the EventLog security descriptor registry value for defense evasion. It leverages data from the Endpoint.Registry data model, focusing on changes to the "CustomSD" value within the "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Eventlog<Channel>\CustomSD" path. This activity is significant as changes to the access permissions of the event log could blind security products and help attackers evade defenses. If confirmed malicious, this could allow attackers to block users and security products from viewing, ingesting and interacting event logs.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Evasion | T1562.002 Impair Defenses: Disable Windows Event Logging |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 13 | RegistryEvent (Value Set) |
Stages and Predicates
Stage 1: tstats
tstats WHERE Registry.registry_path IN ("*\Microsoft\Windows\EventLog\*", "*\\Microsoft\\Windows\\CurrentVersion\\WINEVT\\Channels\\*") Registry.registry_value_name="ChannelAccess" 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.
| Field | Kind | Values |
|---|---|---|
Registry.registry_path | in |
|
Registry.registry_value_name | eq |
|