Detection rules › Sigma

Network Connection Initiated Via Notepad.EXE

Severity
high
Author
EagleEye Team
Source
upstream

Detects a network connection that is initiated by the "notepad.exe" process. This might be a sign of process injection from a beacon process or something similar. Notepad rarely initiates a network communication except when printing documents for example.

MITRE ATT&CK coverage

TacticTechniques
Privilege EscalationT1055 Process Injection
Defense EvasionT1055 Process Injection

Event coverage

ProviderEvent IDTitle
Sysmon3Network connection

Stages and Predicates

Stage 1: selection

Image|endswith: '\notepad.exe'

Stage 2: not 1 of filter_optional_printing

DestinationPort: 9100

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
DestinationPorteq
  • 9100
Imageends_with
  • \notepad.exe corpus 11 (sigma 11)