WEBSHELL_ASPX_Chopper_Like_Mar21_1

rule WEBSHELL_ASPX_Chopper_Like_Mar21_1 {
   meta:
      description = "Detects Chopper like ASPX Webshells"
      author = "Florian Roth (Nextron Systems)"
      reference = "Internal Research"
      date = "2021-03-31"
      score = 85
      hash1 = "ac44513e5ef93d8cbc17219350682c2246af6d5eb85c1b4302141d94c3b06c90"
      id = "a4dc1880-865f-5e20-89a2-3a642c453ef9"
   strings:
      $s1 = "http://f/<script language=\"JScript\" runat=\"server\">var _0x" ascii
      $s2 = "));function Page_Load(){var _0x" ascii
      $s3 = ";eval(Request[_0x" ascii
      $s4 = "','orange','unsafe','" ascii
   condition:
      filesize < 3KB and
      1 of them or 2 of them
}