diff --git a/patches/server/Cache-block-data-strings.patch b/patches/server/Cache-block-data-strings.patch
index 0604aa6c18..8459ad575a 100644
--- a/patches/server/Cache-block-data-strings.patch
+++ b/patches/server/Cache-block-data-strings.patch
@@ -20,6 +20,15 @@ diff --git a/src/main/java/org/bukkit/craftbukkit/block/data/CraftBlockData.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/craftbukkit/block/data/CraftBlockData.java
 +++ b/src/main/java/org/bukkit/craftbukkit/block/data/CraftBlockData.java
+@@ -0,0 +0,0 @@ public class CraftBlockData implements BlockData {
+         return exactMatch;
+     }
+ 
+-    private static final Map<Class<? extends Enum<?>>, Enum<?>[]> ENUM_VALUES = new HashMap<>();
++    private static final Map<Class<? extends Enum<?>>, Enum<?>[]> ENUM_VALUES = new java.util.concurrent.ConcurrentHashMap<>(); // Paper - make thread safe
+ 
+     /**
+      * Convert an NMS Enum (usually a BlockStateEnum) to its appropriate Bukkit
 @@ -0,0 +0,0 @@ public class CraftBlockData implements BlockData {
          Preconditions.checkState(CraftBlockData.MAP.put(nms, bukkit) == null, "Duplicate mapping %s->%s", nms, bukkit);
      }