diff --git a/pkg/core/state/mpt_root.go b/pkg/core/state/mpt_root.go
index 5fd716ff4..0a4e4c183 100644
--- a/pkg/core/state/mpt_root.go
+++ b/pkg/core/state/mpt_root.go
@@ -1,6 +1,9 @@
 package state
 
 import (
+	"encoding/binary"
+
+	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/io"
@@ -9,6 +12,7 @@ import (
 
 // MPTRoot represents storage state root together with sign info.
 type MPTRoot struct {
+	Network netmode.Magic        `json:"-"`
 	Version byte                 `json:"version"`
 	Index   uint32               `json:"index"`
 	Root    util.Uint256         `json:"stateroot"`
@@ -17,9 +21,11 @@ type MPTRoot struct {
 
 // GetSignedPart returns part of MPTRootBase which needs to be signed.
 func (s *MPTRoot) GetSignedPart() []byte {
-	buf := io.NewBufBinWriter()
-	s.EncodeBinaryUnsigned(buf.BinWriter)
-	return buf.Bytes()
+	b := make([]byte, 4+32)
+	binary.LittleEndian.PutUint32(b, uint32(s.Network))
+	h := s.Hash()
+	copy(b[4:], h[:])
+	return b
 }
 
 // GetSignedHash returns hash of MPTRootBase which needs to be signed.
@@ -29,7 +35,9 @@ func (s *MPTRoot) GetSignedHash() util.Uint256 {
 
 // Hash returns hash of s.
 func (s *MPTRoot) Hash() util.Uint256 {
-	return hash.DoubleSha256(s.GetSignedPart())
+	buf := io.NewBufBinWriter()
+	s.EncodeBinaryUnsigned(buf.BinWriter)
+	return hash.Sha256(buf.Bytes())
 }
 
 // DecodeBinaryUnsigned decodes hashable part of state root.
diff --git a/pkg/core/stateroot/module.go b/pkg/core/stateroot/module.go
index 2d63b89b5..49b5b2661 100644
--- a/pkg/core/stateroot/module.go
+++ b/pkg/core/stateroot/module.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"sync"
 
+	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
 	"github.com/nspcc-dev/neo-go/pkg/core/mpt"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
@@ -19,10 +20,11 @@ import (
 type (
 	// Module represents module for local processing of state roots.
 	Module struct {
-		Store *storage.MemCachedStore
-		mpt   *mpt.Trie
-		bc    blockchainer.Blockchainer
-		log   *zap.Logger
+		Store   *storage.MemCachedStore
+		network netmode.Magic
+		mpt     *mpt.Trie
+		bc      blockchainer.Blockchainer
+		log     *zap.Logger
 
 		currentLocal    atomic.Value
 		localHeight     atomic.Uint32
@@ -45,9 +47,10 @@ type (
 // NewModule returns new instance of stateroot module.
 func NewModule(bc blockchainer.Blockchainer, log *zap.Logger, s *storage.MemCachedStore) *Module {
 	return &Module{
-		bc:    bc,
-		log:   log,
-		Store: s,
+		network: bc.GetConfig().Magic,
+		bc:      bc,
+		log:     log,
+		Store:   s,
 	}
 }
 
@@ -113,8 +116,9 @@ func (s *Module) AddMPTBatch(index uint32, b mpt.Batch) error {
 	}
 	s.mpt.Flush()
 	err := s.addLocalStateRoot(&state.MPTRoot{
-		Index: index,
-		Root:  s.mpt.StateRoot(),
+		Network: s.network,
+		Index:   index,
+		Root:    s.mpt.StateRoot(),
 	})
 	if err != nil {
 		return err
diff --git a/pkg/core/stateroot/store.go b/pkg/core/stateroot/store.go
index b2ab7d210..d2f7fd4c4 100644
--- a/pkg/core/stateroot/store.go
+++ b/pkg/core/stateroot/store.go
@@ -46,7 +46,7 @@ func (s *Module) getStateRoot(key []byte) (*state.MPTRoot, error) {
 		return nil, err
 	}
 
-	sr := new(state.MPTRoot)
+	sr := &state.MPTRoot{Network: s.network}
 	r := io.NewBinReaderFromBuf(data)
 	sr.DecodeBinary(r)
 	return sr, r.Err
diff --git a/pkg/core/stateroot_test.go b/pkg/core/stateroot_test.go
index dc9632081..27cad0cd0 100644
--- a/pkg/core/stateroot_test.go
+++ b/pkg/core/stateroot_test.go
@@ -10,6 +10,7 @@ import (
 
 	"github.com/nspcc-dev/neo-go/internal/testserdes"
 	"github.com/nspcc-dev/neo-go/pkg/config"
+	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/native/noderoles"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
@@ -43,7 +44,7 @@ func testSignStateRoot(t *testing.T, r *state.MPTRoot, pubs keys.PublicKeys, acc
 		VerificationScript: script,
 		InvocationScript:   w.Bytes(),
 	}
-	data, err := testserdes.EncodeBinary(stateroot.NewMessage(stateroot.RootT, r))
+	data, err := testserdes.EncodeBinary(stateroot.NewMessage(netmode.UnitTestNet, stateroot.RootT, r))
 	require.NoError(t, err)
 	return data
 }
@@ -96,7 +97,7 @@ func TestStateRoot(t *testing.T) {
 	t.Run("drop zero index", func(t *testing.T) {
 		r, err := srv.GetStateRoot(0)
 		require.NoError(t, err)
-		data, err := testserdes.EncodeBinary(stateroot.NewMessage(stateroot.RootT, r))
+		data, err := testserdes.EncodeBinary(stateroot.NewMessage(netmode.UnitTestNet, stateroot.RootT, r))
 		require.NoError(t, err)
 		require.NoError(t, srv.OnPayload(&payload.Extensible{Data: data}))
 		require.EqualValues(t, 0, srv.CurrentValidatedHeight())
diff --git a/pkg/rpc/server/server_test.go b/pkg/rpc/server/server_test.go
index aa222cb32..a7317d519 100644
--- a/pkg/rpc/server/server_test.go
+++ b/pkg/rpc/server/server_test.go
@@ -1368,7 +1368,7 @@ func testRPCProtocol(t *testing.T, doRPCCall func(string, string, *testing.T) []
 			body := doRPCCall(rpc, httpSrv.URL, t)
 			rawRes := checkErrGetResult(t, body, false)
 
-			res := new(state.MPTRoot)
+			res := &state.MPTRoot{Network: netmode.UnitTestNet}
 			require.NoError(t, json.Unmarshal(rawRes, res))
 			require.NotEqual(t, util.Uint256{}, res.Root) // be sure this test uses valid height
 
diff --git a/pkg/services/stateroot/message.go b/pkg/services/stateroot/message.go
index 5b1e32e73..2e65acf1d 100644
--- a/pkg/services/stateroot/message.go
+++ b/pkg/services/stateroot/message.go
@@ -3,6 +3,7 @@ package stateroot
 import (
 	"fmt"
 
+	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 )
@@ -13,6 +14,7 @@ type (
 
 	// Message represents state-root related message.
 	Message struct {
+		Network netmode.Magic
 		Type    MessageType
 		Payload io.Serializable
 	}
@@ -25,8 +27,9 @@ const (
 )
 
 // NewMessage creates new message of specified type.
-func NewMessage(typ MessageType, p io.Serializable) *Message {
+func NewMessage(net netmode.Magic, typ MessageType, p io.Serializable) *Message {
 	return &Message{
+		Network: net,
 		Type:    typ,
 		Payload: p,
 	}
@@ -44,7 +47,7 @@ func (m *Message) DecodeBinary(r *io.BinReader) {
 	case VoteT:
 		m.Payload = new(Vote)
 	case RootT:
-		m.Payload = new(state.MPTRoot)
+		m.Payload = &state.MPTRoot{Network: m.Network}
 	default:
 		r.Err = fmt.Errorf("invalid type: %x", m.Type)
 		return
diff --git a/pkg/services/stateroot/network.go b/pkg/services/stateroot/network.go
index b5489edc5..a98e1af82 100644
--- a/pkg/services/stateroot/network.go
+++ b/pkg/services/stateroot/network.go
@@ -72,7 +72,7 @@ func (s *service) getIncompleteRoot(height uint32) *incompleteRoot {
 
 func (s *service) sendValidatedRoot(r *state.MPTRoot) {
 	w := io.NewBufBinWriter()
-	m := NewMessage(RootT, r)
+	m := NewMessage(s.Network, RootT, r)
 	m.EncodeBinary(w.BinWriter)
 	ep := &payload.Extensible{
 		Network:         s.Network,
diff --git a/pkg/services/stateroot/service.go b/pkg/services/stateroot/service.go
index 0c5b17f40..55a86ab4e 100644
--- a/pkg/services/stateroot/service.go
+++ b/pkg/services/stateroot/service.go
@@ -61,6 +61,7 @@ const (
 func New(cfg config.StateRoot, log *zap.Logger, bc blockchainer.Blockchainer) (Service, error) {
 	s := &service{
 		StateRoot:       bc.GetStateModule(),
+		Network:         bc.GetConfig().Magic,
 		chain:           bc,
 		log:             log,
 		incompleteRoots: make(map[uint32]*incompleteRoot),
@@ -94,7 +95,7 @@ func New(cfg config.StateRoot, log *zap.Logger, bc blockchainer.Blockchainer) (S
 
 // OnPayload implements Service interface.
 func (s *service) OnPayload(ep *payload.Extensible) error {
-	m := new(Message)
+	m := &Message{Network: s.Network}
 	r := io.NewBinReaderFromBuf(ep.Data)
 	m.DecodeBinary(r)
 	if r.Err != nil {
diff --git a/pkg/services/stateroot/validators.go b/pkg/services/stateroot/validators.go
index b3a98378e..359d2b779 100644
--- a/pkg/services/stateroot/validators.go
+++ b/pkg/services/stateroot/validators.go
@@ -55,7 +55,7 @@ func (s *service) signAndSend(r *state.MPTRoot) error {
 	s.accMtx.RLock()
 	myIndex := s.myIndex
 	s.accMtx.RUnlock()
-	msg := NewMessage(VoteT, &Vote{
+	msg := NewMessage(s.Network, VoteT, &Vote{
 		ValidatorIndex: int32(myIndex),
 		Height:         r.Index,
 		Signature:      sig,