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rule FE_CPE_MS17_010_RANSOMWARE {
meta:version="1.1"
//filetype="PE"
author="Ian.Ahl@fireeye.com @TekDefense, Nicholas.Carr@mandiant.com @ItsReallyNick"
date="2017-06-27"
description="Probable PETYA ransomware using ETERNALBLUE, WMIC, PsExec"
reference = "https://www.fireeye.com/blog/threat-research/2017/06/petya-ransomware-spreading-via-eternalblue-exploit.html"
strings:
// DRIVE USAGE
$dmap01 = "\\\\.\\PhysicalDrive" nocase ascii wide
$dmap02 = "\\\\.\\PhysicalDrive0" nocase ascii wide
$dmap03 = "\\\\.\\C:" nocase ascii wide
$dmap04 = "TERMSRV" nocase ascii wide
$dmap05 = "\\admin$" nocase ascii wide
$dmap06 = "GetLogicalDrives" nocase ascii wide
$dmap07 = "GetDriveTypeW" nocase ascii wide
// RANSOMNOTE
$msg01 = "WARNING: DO NOT TURN OFF YOUR PC!" nocase ascii wide
$msg02 = "IF YOU ABORT THIS PROCESS" nocase ascii wide
$msg03 = "DESTROY ALL OF YOUR DATA!" nocase ascii wide
$msg04 = "PLEASE ENSURE THAT YOUR POWER CABLE IS PLUGGED" nocase ascii wide
$msg05 = "your important files are encrypted" ascii wide
$msg06 = "Your personal installation key" nocase ascii wide
$msg07 = "worth of Bitcoin to following address" nocase ascii wide
$msg08 = "CHKDSK is repairing sector" nocase ascii wide
$msg09 = "Repairing file system on " nocase ascii wide
$msg10 = "Bitcoin wallet ID" nocase ascii wide
$msg11 = "wowsmith123456@posteo.net" nocase ascii wide
$msg12 = "1Mz7153HMuxXTuR2R1t78mGSdzaAtNbBWX" nocase ascii wide
$msg_pcre = /(en|de)crypt(ion|ed\.)/
// FUNCTIONALITY, APIS
$functions01 = "need dictionary" nocase ascii wide
$functions02 = "comspec" nocase ascii wide
$functions03 = "OpenProcessToken" nocase ascii wide
$functions04 = "CloseHandle" nocase ascii wide
$functions05 = "EnterCriticalSection" nocase ascii wide
$functions06 = "ExitProcess" nocase ascii wide
$functions07 = "GetCurrentProcess" nocase ascii wide
$functions08 = "GetProcAddress" nocase ascii wide
$functions09 = "LeaveCriticalSection" nocase ascii wide
$functions10 = "MultiByteToWideChar" nocase ascii wide
$functions11 = "WideCharToMultiByte" nocase ascii wide
$functions12 = "WriteFile" nocase ascii wide
$functions13 = "CoTaskMemFree" nocase ascii wide
$functions14 = "NamedPipe" nocase ascii wide
$functions15 = "Sleep" nocase ascii wide // imported, not in strings
// COMMANDS
// -- Clearing event logs & USNJrnl
$cmd01 = "wevtutil cl Setup" ascii wide nocase
$cmd02 = "wevtutil cl System" ascii wide nocase
$cmd03 = "wevtutil cl Security" ascii wide nocase
$cmd04 = "wevtutil cl Application" ascii wide nocase
$cmd05 = "fsutil usn deletejournal" ascii wide nocase
// -- Scheduled task
$cmd06 = "schtasks " nocase ascii wide
$cmd07 = "/Create /SC " nocase ascii wide
$cmd08 = " /TN " nocase ascii wide
$cmd09 = "at %02d:%02d %ws" nocase ascii wide
$cmd10 = "shutdown.exe /r /f" nocase ascii wide
// -- Sysinternals/PsExec and WMIC
$cmd11 = "-accepteula -s" nocase ascii wide
$cmd12 = "wmic"
$cmd13 = "/node:" nocase ascii wide
$cmd14 = "process call create" nocase ascii wide
condition:
// (uint16(0) == 0x5A4D)
3 of ($dmap*)
and 2 of ($msg*)
and 9 of ($functions*)
and 7 of ($cmd*)
}