Network Connection Initiated via Finger.EXE
Detects network connections via finger.exe, which can be abused by threat actors to retrieve remote commands for execution on Windows devices. In one ClickFix malware campaign, adversaries leveraged the finger protocol to fetch commands from a remote server. Since the finger utility is not commonly used in modern Windows environments, its presence already raises suspicion. Investigating such network connections can also help identify potential malicious infrastructure used by threat actors
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Events for outbound and inbound network connections including DNS resolution.
detection:
selection:
Initiated: 'true'
Image|endswith: '\finger.exe'
condition: selectionFalse positives are unlikely for most environments. High confidence detection.
DNS Query by Finger Utility
Detects DNS queries made by the finger utility, which can be abused by threat actors to retrieve remote commands for execution on Windows devices. In one ClickFix malware campaign, adversaries leveraged the finger protocol to fetch commands from a remote server. Since the finger utility is not commonly used in modern Windows environments, its presence already raises suspicion. Investigating such DNS queries can also help identify potential malicious infrastructure used by threat actors for command and control (C2) communication.
Detects similar activity. Both rules may fire on overlapping events.
Finger.EXE Execution
Detects execution of the "finger.exe" utility. Finger.EXE or "TCPIP Finger Command" is an old utility that is still present on modern Windows installation. It Displays information about users on a specified remote computer (typically a UNIX computer) that is running the finger service or daemon. Due to the old nature of this utility and the rareness of machines having the finger service. Any execution of "finger.exe" can be considered "suspicious" and worth investigating.
Detects similar activity. Both rules may fire on overlapping events.