SEKOIA_Dotnet_Injector_New_Payload

import "dotnet"

rule SEKOIA_Dotnet_Injector_New_Payload : FILE
{
	meta:
		description = "New dotnet injector"
		author = "Sekoia.io"
		id = "b0a1d471-5381-4fa8-8563-7e72ecd15bed"
		date = "2022-12-21"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/dotnet_injector_new_payload.yar#L3-L30"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "8b5e2f6e7947471e10e0ec85eef1cebe1904c2e77b7cfe92e578ebe306041842"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$f1 = "DownloadFile" ascii
		$f2 = "StreamReader" ascii
		$f3 = "ReadToEnd" ascii
		$f4 = "Reverse" ascii
		$f5 = "Load" ascii
		$f6 = "StringToByteArray" ascii
		$s1 = "Admin" wide
		$s2 = "User" wide
		$p1 = "\\Microsoft\\Windows\\Start Menu\\Programs\\Startup\\" wide
		$p2 = ".lnk" wide

	condition:
		filesize < 300KB and all of ( $f* ) and all of ( $s* ) and all of ( $p* ) and dotnet.is_dotnet
}