Detectionhightest

Network Connection Initiated Via Notepad.EXE

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.

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EagleEye TeamCreated Thu May 14Updated Fri Feb 02e81528db-fc02-45e8-8e98-4e84aba1f10bwindows
Log Source
WindowsNetwork Connection
ProductWindows← raw: windows
CategoryNetwork Connection← raw: network_connection

Events for outbound and inbound network connections including DNS resolution.

Detection Logic
Detection Logic2 selectors
detection:
    selection:
        Image|endswith: '\notepad.exe'
    filter_optional_printing:
        DestinationPort: 9100
    condition: selection and not 1 of filter_optional_*
False Positives

Printing documents via notepad might cause communication with the printer via port 9100 or similar.

Rule Metadata
Rule ID
e81528db-fc02-45e8-8e98-4e84aba1f10b
Status
test
Level
high
Type
Detection
Created
Thu May 14
Modified
Fri Feb 02
Path
rules/windows/network_connection/net_connection_win_notepad.yml
Raw Tags
attack.privilege-escalationattack.command-and-controlattack.executionattack.defense-evasionattack.t1055
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