SEKOIA_Luckymouse_Sysupdate_Loader

rule SEKOIA_Luckymouse_Sysupdate_Loader : FILE
{
	meta:
		description = "Detects decryption routine prologue of sysupdate loader"
		author = "Sekoia.io"
		id = "6007e846-d467-4d07-b345-e25191b7c8bc"
		date = "2022-08-19"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/luckymouse_sysupdate_loader.yar#L1-L17"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "9d46b74d8e5f94ecd844cffcd6d0d29eb662374c1d6fbe87acf3c877e5f963b3"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$s1 = { DB D4 33 C9 66 B9 ?? ?? E8 FF FF FF FF }

	condition:
		uint16be( 0 ) == 0x4d5a and filesize < 1MB and all of them
}