Suspicious Finger Client Execution for Command and Control

ATT&CK techniques

Exfiltration

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
- T1048.003Exfiltration Over Unencrypted Non-C2 Protocol
Impact

What it detects

This rule detects execution of the legacy finger.exe client, which adversaries abuse to reach external hosts and exfiltrate command output over the finger protocol. Huntress observed finger used to contact an attacker IP following OWASSRF exploitation of Exchange. Because finger is effectively obsolete on modern networks, any execution warrants investigation.

Reporting behind it

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Suspicious Finger Client Execution for Command and Control

Pivot detection · T1048.003 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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