WebShell_PHP_Web_Kit_v4

rule WebShell_PHP_Web_Kit_v4 {
   meta:
      description = "Detects PAS Tool PHP Web Kit"
      reference = "https://github.com/wordfence/grizzly"
      license = "Detection Rule License 1.1 https://github.com/Neo23x0/signature-base/blob/master/LICENSE"
      author = "Florian Roth (Nextron Systems)"
      date = "2016/01/01"
      id = "a5f915cd-b9c5-5cd3-b0a2-c15f6124737a"
   strings:
      $php = "<?php $"

      $s1 = "(StR_ReplAcE(\"\\n\",'',"
      $s2 = ";if(PHP_VERSION<'5'){" ascii
      $s3 = "=SuBstr_rePlACe(" ascii
   condition:
      uint32(0) == 0x68703f3c and 
      $php at 0 and
      filesize > 8KB and filesize < 100KB and
      2 of ($s*)
}