SEKOIA_Ransomware_Win_Lorenz

rule SEKOIA_Ransomware_Win_Lorenz : FILE
{
	meta:
		description = "Detect the Lorenz ransomware"
		author = "Sekoia.io"
		id = "6936cc61-efe5-4d13-b76f-e808ab331457"
		date = "2022-02-10"
		modified = "2024-12-19"
		reference = "https://www.cybereason.com/blog/cybereason-vs.-lorenz-ransomware"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/ransomware_win_lorenz.yar#L1-L27"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "355de0f172c9e877bbca7f75c0bfb07d83ae7f43e7674a7f84c4e4d519dfa7c0"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.1"
		classification = "TLP:CLEAR"

	strings:
		$s1 = ".onion" ascii
		$s2 = "---===Lorenz. Welcome. Again. ===--" ascii
		$s3 = ".Lorenz.sz40" ascii
		$url1 = "egypghtljedbs3x3ui45tfhosakzb376epl7baq2ruzfyewcypswhgqd.onion" ascii
		$url2 = "lorenzmlwpzgxq736jzseuterytjueszsvznuibanxomlpkyxk6ksoyd.onion" ascii
		$url3 = "vsoonropylvbfqnq2urk7uhaxn7afiwgldnj3ntc743awigojm4p7lid.onion" ascii
		$url4 = "kpb3ss3vwvfejd4g3gvpvqo6ad7nnmvcqoik4mxt2376yu2adlg5fwyd.onion" ascii
		$url5 = "vldkrmiqriwlgm2wuxg42nvc6kqsdzsdhsybn27hyn34d66465fxz7id.onion" ascii

	condition:
		uint16( 0 ) == 0x5a4d and filesize > 900KB and filesize < 1200KB and ( all of ( $s* ) or 1 of ( $url* ) )
}