Detection rules › Sigma

Removal Of Index Value to Hide Schedule Task - Registry

Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects when the "index" value of a scheduled task is removed or deleted from the registry. Which effectively hides it from any tooling such as "schtasks /query"

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1562 Impair Defenses

Event coverage

ProviderEvent IDTitle
Sysmon14RegistryEvent (Key and Value Rename)

Stages and Predicates

Stage 1: selection

TargetObject|contains: Index
TargetObject|contains: '\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tree\'

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
TargetObjectmatch
  • Index corpus 2 (sigma 2)
  • \SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tree\ corpus 3 (sigma 3)