DITEKSHEN_MALWARE_Linux_Ransomexx

rule DITEKSHEN_MALWARE_Linux_Ransomexx : FILE
{
	meta:
		description = "Detects RansomEXX ransomware"
		author = "ditekshen"
		id = "b449afc7-9055-55ed-a876-316d1aea8fee"
		date = "2020-11-06"
		modified = "2024-11-01"
		reference = "https://github.com/ditekshen/detection"
		source_url = "https://github.com/ditekshen/detection/blob/e76c93dcdedff04076380ffc60ea54e45b313635/yara/malware.yar#L3834-L3858"
		license_url = "https://github.com/ditekshen/detection/blob/e76c93dcdedff04076380ffc60ea54e45b313635/LICENSE.txt"
		logic_hash = "c233ccc3e741cb2c53f182c48093e41595a82a3f4e5bdb1dc0204f1f57b96c2a"
		score = 75
		quality = 75
		tags = "FILE"
		clamav_sig = "MALWARE.Linux.Ransomware.RansomEXX"

	strings:
		$c1 = "crtstuff.c" fullword ascii
		$c2 = "cryptor.c" fullword ascii
		$c3 = "ransomware.c" fullword ascii
		$c4 = "logic.c" fullword ascii
		$c5 = "enum_files.c" fullword ascii
		$c6 = "readme.c" fullword ascii
		$c7 = "ctr_drbg.c" fullword ascii
		$s1 = "regenerate_pre_data" fullword ascii
		$s2 = "g_RansomHeader" fullword ascii
		$s3 = "CryptOneBlock" fullword ascii
		$s4 = "RansomLogic" fullword ascii
		$s5 = "CryptOneFile" fullword ascii
		$s6 = "encrypt_worker" fullword ascii
		$s7 = "list_dir" fullword ascii
		$s8 = "ctr_drbg_update_internal" fullword ascii

	condition:
		uint16( 0 ) == 0x457f and ( 5 of ( $c* ) or 6 of ( $s* ) or ( 3 of ( $c* ) and 3 of ( $s* ) ) )
}