LoFP LoFP / changes to windows services or a rarely executed child process.

Techniques

Sample rules

Unusual Service Host Child Process - Childless Service

Description

Identifies unusual child processes of Service Host (svchost.exe) that traditionally do not spawn any child processes. This may indicate a code injection or an equivalent form of exploitation.

Detection logic

process where host.os.type == "windows" and event.type == "start" and
  process.parent.name : "svchost.exe" and

  /* based on svchost service arguments -s svcname where the service is known to be childless */
  process.parent.args : (
    "WdiSystemHost", "LicenseManager", "StorSvc", "CDPSvc", "cdbhsvc", "BthAvctpSvc", "SstpSvc", "WdiServiceHost",
    "imgsvc", "TrkWks", "WpnService", "IKEEXT", "PolicyAgent", "CryptSvc", "netprofm", "ProfSvc", "StateRepository",
    "camsvc", "LanmanWorkstation", "NlaSvc", "EventLog", "hidserv", "DisplayEnhancementService", "ShellHWDetection",
    "AppHostSvc", "fhsvc", "CscService", "PushToInstall"
  ) and

  /* unknown FPs can be added here */
  not process.name : ("WerFault.exe", "WerFaultSecure.exe", "wermgr.exe") and
  not (process.executable : "?:\\Windows\\System32\\RelPost.exe" and process.parent.args : "WdiSystemHost") and
  not (
    process.name : "rundll32.exe" and
    process.args : "?:\\WINDOWS\\System32\\winethc.dll,ForceProxyDetectionOnNextRun" and
    process.parent.args : "WdiServiceHost"
  ) and
  not (
    process.executable : (
      "?:\\Program Files\\*",
      "?:\\Program Files (x86)\\*",
      "?:\\Windows\\System32\\Kodak\\kds_?????\\lib\\lexexe.exe"
    ) and process.parent.args : "imgsvc"
  )