Detection rules › Splunk
Windows Registry Delete Task SD
The following analytic detects a process attempting to delete a scheduled task's Security Descriptor (SD) from the registry path of that task. It leverages the Endpoint.Registry data model to identify registry actions performed by the SYSTEM user, specifically targeting deletions of the SD value. This activity is significant as it may indicate an attempt to remove evidence of a scheduled task for defense evasion. If confirmed malicious, it suggests an attacker with privileged access trying to hide their tracks, potentially compromising system integrity and security.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1053.005 Scheduled Task/Job: Scheduled Task |
| Persistence | T1053.005 Scheduled Task/Job: Scheduled Task |
| Privilege Escalation | T1053.005 Scheduled Task/Job: Scheduled Task |
| Defense Evasion | T1562 Impair Defenses |
Event coverage
| Provider | Event ID | Title |
|---|---|---|
| Sysmon | 12 | RegistryEvent (Object create and delete) |
Stages and Predicates
Stage 1: tstats
tstats WHERE (Registry.registry_key_name="SD" OR Registry.registry_value_name="SD") Registry.action="deleted" Registry.registry_path="*\\Schedule\\TaskCache\\Tree\\*" Registry.user="SYSTEM" 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.
| Field | Kind | Values |
|---|---|---|
Registry.action | eq |
|
Registry.registry_key_name | eq |
|
Registry.registry_path | in |
|
Registry.registry_value_name | eq |
|
Registry.user | eq |
|