Visual Studio Code Tunnel Execution (Sysmon)

id: '40420.73844'
title: Visual Studio Code Tunnel Execution
description: Adversaries may communicate using application layer protocols associated
  with web traffic to avoid detection/network filtering by blending in with existing
  traffic. Commands to the remote system, and often the results of those commands,
  will be embedded within the protocol traffic between the client and server. This
  use case detects the execution of Visual Studio Code tunnel in attempt to establish
  a C2 channel, accounting for instances where the binary has been renamed.
logic_format: Splunk
logic: ' `get_endpoint_data` `get_endpoint_data_sysmon` (TERM(EventCode=1) OR "<EventID>1<")
  (".exe" "tunnel") OR (".exe" "tunnel" "--name " "--accept-server-license-terms")
  OR (" tunnel" "cmd.exe" "/d" "/c" "\servers\Stable-" "code-server.cmd") | where
  match(process, "(?i)\.exe\s+tunnel$") or (match(process, "(?i)\.exe\s+tunnel") and
  match(process, "(?i)--name\s+") and match(process, "(?i)--accept-server-license-terms"))
  or (match(parent_process, "(?i)\stunnel$") and match(process_name, "(?i)cmd\.exe")
  and match(process, "\s/d\s") and match(process, "\s/c\s") and match(process, "(?i)\x5cservers\x5cStable-")
  and match(process, "(?i)code-server\.cmd")) | table _time, host, user, process,
  process_*, parent_* | bin span=1s | stats values(*) as * by _time, host '
techniques:
- command-and-control:application layer protocol:web protocols
technique_id:
- T1071.001
data_category:
- Windows Sysmon
references:
- https://detection.fyi/sigmahq/sigma/windows/process_creation/proc_creation_win_vscode_tunnel_execution/
- https://attack.mitre.org/techniques/T1071/001/
- https://www.sentinelone.com/labs/operation-digital-eye-chinese-apt-compromises-critical-digital-infrastructure-via-visual-studio-code-tunnels/