diff --git a/acl/grpc/types_frostfs.pb.go b/acl/grpc/types_frostfs.pb.go
index e5a6f32..bc90cb7 100644
Binary files a/acl/grpc/types_frostfs.pb.go and b/acl/grpc/types_frostfs.pb.go differ
diff --git a/ape/grpc/types_frostfs.pb.go b/ape/grpc/types_frostfs.pb.go
index cf9499f..1f2a1a5 100644
Binary files a/ape/grpc/types_frostfs.pb.go and b/ape/grpc/types_frostfs.pb.go differ
diff --git a/apemanager/grpc/service_frostfs.pb.go b/apemanager/grpc/service_frostfs.pb.go
index 7f3ed10..b2633e1 100644
Binary files a/apemanager/grpc/service_frostfs.pb.go and b/apemanager/grpc/service_frostfs.pb.go differ
diff --git a/container/grpc/types_frostfs.pb.go b/container/grpc/types_frostfs.pb.go
index 4ca23fa..a4f0882 100644
Binary files a/container/grpc/types_frostfs.pb.go and b/container/grpc/types_frostfs.pb.go differ
diff --git a/netmap/grpc/types_frostfs.pb.go b/netmap/grpc/types_frostfs.pb.go
index 0328531..24003c6 100644
Binary files a/netmap/grpc/types_frostfs.pb.go and b/netmap/grpc/types_frostfs.pb.go differ
diff --git a/object/grpc/service_frostfs.pb.go b/object/grpc/service_frostfs.pb.go
index 9ee5a3d..a55a41b 100644
Binary files a/object/grpc/service_frostfs.pb.go and b/object/grpc/service_frostfs.pb.go differ
diff --git a/object/grpc/types_frostfs.pb.go b/object/grpc/types_frostfs.pb.go
index e4a916f..a6d4f01 100644
Binary files a/object/grpc/types_frostfs.pb.go and b/object/grpc/types_frostfs.pb.go differ
diff --git a/refs/grpc/types_frostfs.pb.go b/refs/grpc/types_frostfs.pb.go
index 5a16f8e..f2a2663 100644
Binary files a/refs/grpc/types_frostfs.pb.go and b/refs/grpc/types_frostfs.pb.go differ
diff --git a/session/grpc/service_frostfs.pb.go b/session/grpc/service_frostfs.pb.go
index 6d3ea9f..26213b9 100644
Binary files a/session/grpc/service_frostfs.pb.go and b/session/grpc/service_frostfs.pb.go differ
diff --git a/session/grpc/types_frostfs.pb.go b/session/grpc/types_frostfs.pb.go
index e9f3b42..542a02b 100644
Binary files a/session/grpc/types_frostfs.pb.go and b/session/grpc/types_frostfs.pb.go differ
diff --git a/status/grpc/types_frostfs.pb.go b/status/grpc/types_frostfs.pb.go
index 1d8b477..6c62a0f 100644
Binary files a/status/grpc/types_frostfs.pb.go and b/status/grpc/types_frostfs.pb.go differ
diff --git a/tombstone/grpc/types_frostfs.pb.go b/tombstone/grpc/types_frostfs.pb.go
index acb1836..e56832a 100644
Binary files a/tombstone/grpc/types_frostfs.pb.go and b/tombstone/grpc/types_frostfs.pb.go differ
diff --git a/util/proto/marshal_test.go b/util/proto/marshal_test.go
index 5498cf9..29af711 100644
--- a/util/proto/marshal_test.go
+++ b/util/proto/marshal_test.go
@@ -50,9 +50,6 @@ func TestStableMarshalSingle(t *testing.T) {
 
 			var actualFrostfs generated.Primitives
 			require.NoError(t, actualFrostfs.UnmarshalJSON(r))
-			if len(actualFrostfs.FieldA) == 0 {
-				actualFrostfs.FieldA = nil
-			}
 			require.Equal(t, input, &actualFrostfs)
 
 			primitivesEqual(t, input, &actual)
@@ -110,9 +107,6 @@ func TestStableMarshalSingle(t *testing.T) {
 
 				var actualFrostfs generated.Primitives
 				require.NoError(t, actualFrostfs.UnmarshalJSON(r))
-				if len(actualFrostfs.FieldA) == 0 {
-					actualFrostfs.FieldA = nil
-				}
 				require.Equal(t, tc.input, &actualFrostfs)
 
 				primitivesEqual(t, tc.input, &actual)
@@ -124,9 +118,7 @@ func TestStableMarshalSingle(t *testing.T) {
 func primitivesEqual(t *testing.T, a *generated.Primitives, b *test.Primitives) {
 	// Compare each field directly, because proto-generated code has private fields.
 	require.Equal(t, len(a.FieldA), len(b.FieldA))
-	if len(a.FieldA) != 0 {
-		require.Equal(t, a.FieldA, b.FieldA)
-	}
+	require.Equal(t, a.FieldA, b.FieldA)
 	require.Equal(t, a.FieldB, b.FieldB)
 	require.Equal(t, a.FieldC, b.FieldC)
 	require.Equal(t, a.FieldD, b.FieldD)
diff --git a/util/proto/test/custom/test_frostfs.pb.go b/util/proto/test/custom/test_frostfs.pb.go
index f979038..5ef95a6 100644
Binary files a/util/proto/test/custom/test_frostfs.pb.go and b/util/proto/test/custom/test_frostfs.pb.go differ
diff --git a/util/protogen/internalgengo/json.go b/util/protogen/internalgengo/json.go
index 15facfd..55c9cd3 100644
--- a/util/protogen/internalgengo/json.go
+++ b/util/protogen/internalgengo/json.go
@@ -129,7 +129,17 @@ func emitJSONFieldRead(g *protogen.GeneratedFile, f *protogen.Field, name string
 	case protoreflect.StringKind:
 		template = "%s = in.String()"
 	case protoreflect.BytesKind:
-		template = "%s = in.Bytes()"
+		// Since some time ago proto3 support optional keyword, thus the presence is not tracked by default:
+		// https://github.com/protocolbuffers/protobuf-go/blob/fb995f184a1719ec42b247a3771d1036d92adf67/internal/impl/message_reflect_field.go#L327
+		// We do not explicitly support `optional` keyword, protoc will fail on such fileds.
+		// Thus, treat empty string as `[]byte(nil)`.
+		template = `{
+			tmp := in.Bytes()
+			if len(tmp) == 0 {
+				tmp = nil
+			}
+			%s = tmp
+		}`
 	case protoreflect.MessageKind:
 		if f.Desc.IsList() {
 			g.P("f = ", fieldType(g, f)[2:], "{}")