CmdID

CmdID / Rules / Windows

Kalambur Backdoor Curl TOR SOCKS Proxy Execution

A Sigma rule for process creation on Windows, from SigmaHQ’s emerging threats rules, by Arda Buyukkaya (EclecticIQ).

high 4 ATT&CK techniques 1 program it names

What it looks for

its detection, as SigmaHQ writes it
detection:
  selection_img:
    Image|endswith: '\curl.exe'
  selection_onion:
    CommandLine|contains: '.onion'
  selection_socks:
    CommandLine|contains:
      - 'socks5h://'
      - 'socks5://'
      - 'socks4a://'
  condition: all of selection_*

The rule’s detection, its selections and fields in order of name. The whole rule, with its references and false positives, is on SigmaHQ, by Arda Buyukkaya (EclecticIQ), under the Detection Rule License 1.1. CmdID evaluates it on a command line alone: a test on what a command line cannot show, such as the parent process or the user, is not met.

None of the everyday examples and documented commands on CmdID’s program pages trips it. To see whether a command line does, paste it into CmdID.

Programs and files it names

their pages here

ATT&CK

the techniques it is tagged with
T1059.001Command and Scripting Interpreter: PowerShell
T1071.001Application Layer Protocol: Web Protocols
T1090Proxy
T1573Encrypted Channel