signature-base/yara/gen_osx_evilosx.yar

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rule OSX_backdoor_EvilOSX {
meta:
description = "EvilOSX MacOS/OSX backdoor"
author = "John Lambert @JohnLaTwC"
reference = "https://github.com/Marten4n6/EvilOSX, https://twitter.com/JohnLaTwC/status/966139336436498432"
date = "2018-02-23"
hash = "89e5b8208daf85f549d9b7df8e2a062e47f15a5b08462a4224f73c0a6223972a"
strings:
$h1 = /#!\/usr\/bin\/env\s+python/
$s0 = "import base64" fullword ascii
$s1 = "b64decode" fullword ascii
//strings present in decoded python script:
$x0 = "EvilOSX" fullword ascii
$x1 = "get_launch_agent_directory" fullword ascii
//Base64 encoded versions of these strings
//EvilOSX
$enc_x0 = /(AHYAaQBsAE8AUwBYA|dmlsT1NY|RQB2AGkAbABPAFMAWA|RXZpbE9TW|UAdgBpAGwATwBTAFgA|V2aWxPU1)/ ascii
//get_launch_agent_directory
$enc_x1 = /(AGUAdABfAGwAYQB1AG4AYwBoAF8AYQBnAGUAbgB0AF8AZABpAHIAZQBjAHQAbwByAHkA|cAZQB0AF8AbABhAHUAbgBjAGgAXwBhAGcAZQBuAHQAXwBkAGkAcgBlAGMAdABvAHIAeQ|dldF9sYXVuY2hfYWdlbnRfZGlyZWN0b3J5|Z2V0X2xhdW5jaF9hZ2VudF9kaXJlY3Rvcn|ZwBlAHQAXwBsAGEAdQBuAGMAaABfAGEAZwBlAG4AdABfAGQAaQByAGUAYwB0AG8AcgB5A|ZXRfbGF1bmNoX2FnZW50X2RpcmVjdG9ye)/ ascii
condition:
$h1 at 0
and filesize < 30KB
and all of ($s*)
and
1 of ($x*)
or 1 of ($enc_x*)
}