diff --git a/proxy/vmess/protocol/vmess.go b/proxy/vmess/protocol/vmess.go
index 84fe1bc4d..cb8545295 100644
--- a/proxy/vmess/protocol/vmess.go
+++ b/proxy/vmess/protocol/vmess.go
@@ -34,9 +34,9 @@ const (
 type VMessRequest struct {
 	Version        byte
 	UserId         user.ID
-	RequestIV      [16]byte
-	RequestKey     [16]byte
-	ResponseHeader [4]byte
+	RequestIV      []byte
+	RequestKey     []byte
+	ResponseHeader []byte
 	Command        byte
 	Address        v2net.Address
 }
@@ -102,9 +102,9 @@ func (r *VMessRequestReader) Read(reader io.Reader) (*VMessRequest, error) {
 		return nil, errors.NewProtocolVersionError(int(request.Version))
 	}
 
-	copy(request.RequestIV[:], buffer[1:17])       // 16 bytes
-	copy(request.RequestKey[:], buffer[17:33])     // 16 bytes
-	copy(request.ResponseHeader[:], buffer[33:37]) // 4 bytes
+	request.RequestIV = buffer[1:17]       // 16 bytes
+	request.RequestKey = buffer[17:33]     // 16 bytes
+	request.ResponseHeader = buffer[33:37] // 4 bytes
 	request.Command = buffer[37]
 
 	port := binary.BigEndian.Uint16(buffer[38:40])
@@ -169,9 +169,9 @@ func (request *VMessRequest) ToBytes(idHash user.CounterHash, randomRangeInt64 u
 	encryptionBegin := len(buffer)
 
 	buffer = append(buffer, request.Version)
-	buffer = append(buffer, request.RequestIV[:]...)
-	buffer = append(buffer, request.RequestKey[:]...)
-	buffer = append(buffer, request.ResponseHeader[:]...)
+	buffer = append(buffer, request.RequestIV...)
+	buffer = append(buffer, request.RequestKey...)
+	buffer = append(buffer, request.ResponseHeader...)
 	buffer = append(buffer, request.Command)
 	buffer = append(buffer, request.Address.PortBytes()...)
 
diff --git a/proxy/vmess/protocol/vmess_test.go b/proxy/vmess/protocol/vmess_test.go
index b89604c51..c27d48836 100644
--- a/proxy/vmess/protocol/vmess_test.go
+++ b/proxy/vmess/protocol/vmess_test.go
@@ -26,20 +26,12 @@ func TestVMessSerialization(t *testing.T) {
 	request.Version = byte(0x01)
 	request.UserId = userId
 
-	_, err = rand.Read(request.RequestIV[:])
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	_, err = rand.Read(request.RequestKey[:])
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	_, err = rand.Read(request.ResponseHeader[:])
-	if err != nil {
-		t.Fatal(err)
-	}
+	randBytes := make([]byte, 36)
+	_, err = rand.Read(randBytes)
+	assert.Error(err).IsNil()
+	request.RequestIV = randBytes[:16]
+	request.RequestKey = randBytes[16:32]
+	request.ResponseHeader = randBytes[32:]
 
 	request.Command = byte(0x01)
 	request.Address = v2net.DomainAddress("v2ray.com", 80)
@@ -61,9 +53,9 @@ func TestVMessSerialization(t *testing.T) {
 
 	assert.Byte(actualRequest.Version).Named("Version").Equals(byte(0x01))
 	assert.String(actualRequest.UserId.String).Named("UserId").Equals(request.UserId.String)
-	assert.Bytes(actualRequest.RequestIV[:]).Named("RequestIV").Equals(request.RequestIV[:])
-	assert.Bytes(actualRequest.RequestKey[:]).Named("RequestKey").Equals(request.RequestKey[:])
-	assert.Bytes(actualRequest.ResponseHeader[:]).Named("ResponseHeader").Equals(request.ResponseHeader[:])
+	assert.Bytes(actualRequest.RequestIV).Named("RequestIV").Equals(request.RequestIV[:])
+	assert.Bytes(actualRequest.RequestKey).Named("RequestKey").Equals(request.RequestKey[:])
+	assert.Bytes(actualRequest.ResponseHeader).Named("ResponseHeader").Equals(request.ResponseHeader[:])
 	assert.Byte(actualRequest.Command).Named("Command").Equals(request.Command)
 	assert.String(actualRequest.Address.String()).Named("Address").Equals(request.Address.String())
 }
@@ -77,9 +69,11 @@ func BenchmarkVMessRequestWriting(b *testing.B) {
 	request.Version = byte(0x01)
 	request.UserId = userId
 
-	rand.Read(request.RequestIV[:])
-	rand.Read(request.RequestKey[:])
-	rand.Read(request.ResponseHeader[:])
+	randBytes := make([]byte, 36)
+	rand.Read(randBytes)
+	request.RequestIV = randBytes[:16]
+	request.RequestKey = randBytes[16:32]
+	request.ResponseHeader = randBytes[32:]
 
 	request.Command = byte(0x01)
 	request.Address = v2net.DomainAddress("v2ray.com", 80)
diff --git a/proxy/vmess/vmessout.go b/proxy/vmess/vmessout.go
index abac9c621..8ad1ab84a 100644
--- a/proxy/vmess/vmessout.go
+++ b/proxy/vmess/vmessout.go
@@ -80,9 +80,12 @@ func (handler *VMessOutboundHandler) Dispatch(firstPacket v2net.Packet, ray core
 		Command: command,
 		Address: firstPacket.Destination().Address(),
 	}
-	rand.Read(request.RequestIV[:])
-	rand.Read(request.RequestKey[:])
-	rand.Read(request.ResponseHeader[:])
+
+	buffer := make([]byte, 36) // 16 + 16 + 4
+	rand.Read(buffer)
+	request.RequestIV = buffer[:16]
+	request.RequestKey = buffer[16:32]
+	request.ResponseHeader = buffer[32:]
 
 	go startCommunicate(request, vNextAddress, ray, firstPacket)
 	return nil