Elastic medium stable eql

Encrypting Files with WinRar or 7z

Identifies the use of WinRAR or 7-Zip to create encrypted archives. Adversaries often compress and encrypt data in preparation for exfiltration.

View Source

Detection Logic

process where host.os.type == "windows" and event.type == "start" and
(
  (
    (
      process.name : ("rar.exe", "WinRAR.exe") or ?process.code_signature.subject_name == "win.rar GmbH" or
      ?process.pe.original_file_name == "WinRAR.exe"
    ) and
    process.args == "a" and process.args : ("-hp*", "-p*", "/hp*", "/p*")
  ) or
  (
    (process.name : ("7z.exe", "7za.exe") or ?process.pe.original_file_name in ("7z.exe", "7za.exe")) and
    process.args == "a" and process.args : "-p*"
  )
) and
  not process.parent.executable : (
        "C:\\Program Files\\*.exe",
        "C:\\Program Files (x86)\\*.exe",
        "?:\\ManageEngine\\*\\jre\\bin\\java.exe",
        "?:\\Nox\\bin\\Nox.exe",
        "\\Device\\HarddiskVolume?\\Program Files\\*.exe",
        "\\Device\\HarddiskVolume?\\Program Files (x86)\\*.exe",
        "\\Device\\HarddiskVolume?\\ManageEngine\\*\\jre\\bin\\java.exe",
        "\\Device\\HarddiskVolume?\\Nox\\bin\\Nox.exe"
      )

Field Validations

Loading…

Comments (0)

Loading comments...