Detectionhightest
Suspicious Network Connection Binary No CommandLine
Detects suspicious network connections made by a well-known Windows binary run with no command line parameters
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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 Logic3 selectors
detection:
selection:
Initiated: 'true'
Image|endswith:
- '\regsvr32.exe'
- '\rundll32.exe'
- '\dllhost.exe'
CommandLine|endswith:
- '\regsvr32.exe'
- '\rundll32.exe'
- '\dllhost.exe'
filter_no_cmdline:
CommandLine: ''
filter_null: # e.g. Sysmon has no CommandLine field in network events with ID 3
CommandLine: null
condition: selection and not 1 of filter*False Positives
Unknown
False positive likelihood has not been assessed. Additional context may be needed during triage.
References
MITRE ATT&CK
Tactics
Rule Metadata
Rule ID
20384606-a124-4fec-acbb-8bd373728613
Status
test
Level
high
Type
Detection
Created
Sun Jul 03
Path
rules/windows/network_connection/net_connection_win_susp_binary_no_cmdline.yml
Raw Tags
attack.defense-evasion