SEKOIA_Apt_Unknown_Sessionmanageriis_Strings

rule SEKOIA_Apt_Unknown_Sessionmanageriis_Strings : FILE
{
	meta:
		description = "Detects the IIS SessionManager backdoor"
		author = "Sekoia.io"
		id = "7d55dd82-509f-444d-a1ba-6417b51f392f"
		date = "2022-07-04"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_unknown_sessionmanageriis_strings.yar#L1-L23"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "b1058b07c8e40431f8f3841b5ad49b4d6ead21a91d014f24c083f37eeacc5ac5"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "Wokring OK"
		$ = "Delete File Success :"
		$ = "Delete File Error :"
		$ = "SM_SESSION="
		$ = "SM_SESSIONID"
		$ = "attachment; filename ="
		$ = "CHttpModule::"

	condition:
		uint16be( 0 ) == 0x4d5a and filesize > 100KB and filesize < 400KB and 4 of them
}