Elastic medium stable eql

Execution of Persistent Suspicious Program

Identifies execution of suspicious persistent programs (scripts, rundll32, etc.) by looking at process lineage and command line usage.

View Source

Detection Logic

/* userinit followed by explorer followed by early child process of explorer (unlikely to be launched interactively) within 1m */
sequence by host.id, user.name with maxspan=1m
  [process where host.os.type == "windows" and event.type == "start" and process.name : "userinit.exe" and process.parent.name : "winlogon.exe"]
  [process where host.os.type == "windows" and event.type == "start" and process.name : "explorer.exe"]
  [process where host.os.type == "windows" and event.type == "start" and process.parent.name : "explorer.exe" and
   /* add suspicious programs here */
   process.pe.original_file_name in ("cscript.exe",
                                     "wscript.exe",
                                     "PowerShell.EXE",
                                     "MSHTA.EXE",
                                     "RUNDLL32.EXE",
                                     "REGSVR32.EXE",
                                     "RegAsm.exe",
                                     "MSBuild.exe",
                                     "InstallUtil.exe") and
    /* add potential suspicious paths here */
    process.args : ("C:\\Users\\*", "C:\\ProgramData\\*", "C:\\Windows\\Temp\\*", "C:\\Windows\\Tasks\\*", "C:\\PerfLogs\\*", "C:\\Intel\\*")
   ]

Field Validations

Loading…

Comments (0)

Loading comments...