SEKOIA_Apt_Gamaredon_Gammaload_Malicioushta

rule SEKOIA_Apt_Gamaredon_Gammaload_Malicioushta : FILE
{
	meta:
		description = "Detects Gamaredon's GammaLoad HTA"
		author = "Sekoia.io"
		id = "e5e502db-7f37-40f2-9ba3-81e158e767db"
		date = "2022-08-01"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_gamaredon_gammaload_malicioushta.yar#L1-L21"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "e41ce63e7c6df2edb548ddc57d51af914dab9200e37eb12463169d587205aa7a"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$s1 = "platform = window.navigator?.userAgentData?.platform" ascii fullword
		$s2 = "'Win32', 'Win64', 'Windows', 'WinCE'" ascii
		$s3 = "dcreate.download ="
		$s4 = "dcreate.href = 'data:application/x-rar-compressed;base64"
		$s5 = "= \"UmFyI"

	condition:
		uint32be( 0 ) == 0x3c68746d and filesize < 400KB and filesize > 50KB and 4 of them
}