diff --git a/composer.lock b/composer.lock
index 55c86608e..83a6d6ca0 100644
--- a/composer.lock
+++ b/composer.lock
@@ -254,12 +254,12 @@
             "source": {
                 "type": "git",
                 "url": "https://github.com/pmmp/BedrockBlockUpgradeSchema.git",
-                "reference": "63f5f5e02e952ffa196a4c0671d7fcf8b8cdd9a4"
+                "reference": "b0cc441e029cf5a6de5b05dd0f5657208855232b"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/pmmp/BedrockBlockUpgradeSchema/zipball/63f5f5e02e952ffa196a4c0671d7fcf8b8cdd9a4",
-                "reference": "63f5f5e02e952ffa196a4c0671d7fcf8b8cdd9a4",
+                "url": "https://api.github.com/repos/pmmp/BedrockBlockUpgradeSchema/zipball/b0cc441e029cf5a6de5b05dd0f5657208855232b",
+                "reference": "b0cc441e029cf5a6de5b05dd0f5657208855232b",
                 "shasum": ""
             },
             "default-branch": true,
@@ -273,7 +273,7 @@
                 "issues": "https://github.com/pmmp/BedrockBlockUpgradeSchema/issues",
                 "source": "https://github.com/pmmp/BedrockBlockUpgradeSchema/tree/master"
             },
-            "time": "2022-08-07T19:29:31+00:00"
+            "time": "2023-02-01T21:11:39+00:00"
         },
         {
             "name": "pocketmine/bedrock-data",
diff --git a/src/data/bedrock/block/upgrade/BlockIdMetaUpgrader.php b/src/data/bedrock/block/upgrade/BlockIdMetaUpgrader.php
index ef8267295..972362b86 100644
--- a/src/data/bedrock/block/upgrade/BlockIdMetaUpgrader.php
+++ b/src/data/bedrock/block/upgrade/BlockIdMetaUpgrader.php
@@ -24,7 +24,8 @@ declare(strict_types=1);
 namespace pocketmine\data\bedrock\block\upgrade;
 
 use pocketmine\data\bedrock\block\BlockStateData;
-use pocketmine\network\mcpe\protocol\serializer\NetworkNbtSerializer;
+use pocketmine\nbt\LittleEndianNbtSerializer;
+use pocketmine\utils\BinaryDataException;
 use pocketmine\utils\BinaryStream;
 
 /**
@@ -75,15 +76,24 @@ final class BlockIdMetaUpgrader{
 		$mappingTable = [];
 
 		$legacyStateMapReader = new BinaryStream($data);
-		$nbtReader = new NetworkNbtSerializer();
-		while(!$legacyStateMapReader->feof()){
-			$id = $legacyStateMapReader->get($legacyStateMapReader->getUnsignedVarInt());
-			$meta = $legacyStateMapReader->getLShort();
+		$nbtReader = new LittleEndianNbtSerializer();
 
-			$offset = $legacyStateMapReader->getOffset();
-			$state = $nbtReader->read($legacyStateMapReader->getBuffer(), $offset)->mustGetCompoundTag();
-			$legacyStateMapReader->setOffset($offset);
-			$mappingTable[$id][$meta] = $blockStateUpgrader->upgrade(BlockStateData::fromNbt($state));
+		$idCount = $legacyStateMapReader->getUnsignedVarInt();
+		for($idIndex = 0; $idIndex < $idCount; $idIndex++){
+			$id = $legacyStateMapReader->get($legacyStateMapReader->getUnsignedVarInt());
+
+			$metaCount = $legacyStateMapReader->getUnsignedVarInt();
+			for($metaIndex = 0; $metaIndex < $metaCount; $metaIndex++){
+				$meta = $legacyStateMapReader->getUnsignedVarInt();
+
+				$offset = $legacyStateMapReader->getOffset();
+				$state = $nbtReader->read($legacyStateMapReader->getBuffer(), $offset)->mustGetCompoundTag();
+				$legacyStateMapReader->setOffset($offset);
+				$mappingTable[$id][$meta] = $blockStateUpgrader->upgrade(BlockStateData::fromNbt($state));
+			}
+		}
+		if(!$legacyStateMapReader->feof()){
+			throw new BinaryDataException("Unexpected trailing data in legacy state map data");
 		}
 
 		return new self($mappingTable, $idMap);