SEKOIA_Tool_Gost_Tunnel_Strings

rule SEKOIA_Tool_Gost_Tunnel_Strings : FILE
{
	meta:
		description = "Detects GOST Go Tunnel, based on strings"
		author = "Sekoia.io"
		id = "2de7aae9-9cf8-4007-aa27-5caea4123713"
		date = "2023-02-28"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/tool_gost_tunnel_strings.yar#L1-L35"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "eba1557acc1d9f16817a4bcd24631334a12357e45ad23f1c333de686f20f9291"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = ".(*shadowUDPHandler).transportUDP" ascii
		$ = ".(*quicCipherConn).decrypt" ascii
		$ = ".(*socks4aConnector).ConnectContext.func1" ascii
		$ = ".(*mtlsTransporter).Handshake" ascii
		$ = ".(*FIFOStrategy).Apply" ascii
		$ = ".dnsTCPExchanger" ascii
		$ = ".dohResponseWriter" ascii
		$ = ".tcpRemoteForwardListener" ascii
		$ = ".shadowUDPPacketConn" ascii
		$ = ".sshTunnelListener" ascii
		$ = "/listener/rtcp/listener.go" ascii
		$ = "/handler/unix/handler.go" ascii
		$ = "/handler/tunnel/tunnel.go" ascii
		$ = "/internal/net/proxyproto/listener.go" ascii
		$ = "/internal/util/serial/conn.go" ascii
		$ = "github.com/go-gost/x" ascii

	condition:
		( uint32be( 0 ) == 0x7f454c46 or uint16be( 0 ) == 0x4d5a or uint32be( 0 ) == 0xcefaedfe or uint32be( 0 ) == 0xcffaedfe or uint32be( 0 ) == 0xbebafeca ) and 5 of them
}