signature-base/yara/gen_unicorn_obfuscated_powershell.yar
2018-03-08 18:24:10 +01:00

22 lines
748 B
Plaintext

rule gen_unicorn_obfuscated_powershell {
meta:
description = "PowerShell payload obfuscated by Unicorn toolkit"
author = "John Lambert @JohnLaTwC"
date = "2018-03-07"
hash = "b93d2fe6a671a6a967f31d5b3a0a16d4f93abcaf25188a2bbdc0894087adb10d"
reference = "https://github.com/trustedsec/unicorn/"
strings:
$h1 = "powershell"
$s1 = ".value.toString() 'JAB"
$s2 = "-w 1 -C \"sv"
condition:
filesize < 20KB
and uint32be(0) == 0x706f7765
and $h1 at 0
and (
uint16be(filesize-2) == 0x2722 or /* Footer 1 */
( uint16be(filesize-2) == 0x220a and uint8(filesize-3) == 0x27 ) /* Footer 2 */
)
and all of ($s*)
}