Detection rules › Sigma

Dllhost.EXE Execution Anomaly

Severity
high
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects a "dllhost" process spawning with no commandline arguments which is very rare to happen and could indicate process injection activity or malware mimicking similar system processes.

MITRE ATT&CK coverage

TacticTechniques
Privilege EscalationT1055 Process Injection
Defense EvasionT1055 Process Injection

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.

Stages and Predicates

Stage 1: selection

CommandLine: [dllhost, dllhost.exe]
Image|endswith: '\dllhost.exe'

Stage 2: not 1 of filter_main_null

CommandLine: null

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
CommandLineeq
  • dllhost
  • dllhost.exe
Imageends_with
  • \dllhost.exe corpus 8 (sigma 8)