diff --git a/CHANGELOG.md b/CHANGELOG.md
index 121cb25a..49ffe302 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,7 @@
 This is the rolling changelog for TShock for Terraria. Use past tense when adding new entries; sign your name off when you add or change something. This should primarily be things like user changes, not necessarily codebase changes unless it's really relevant or large.
 
 ## Upcoming Changes
-* Your change goes here!
+* Handling SyncCavernMonsterType packet to prevent an exploit where players could modify the server's cavern monster types and make the server spawn any NPCs - including bosses - onto other players.
 
 ## TShock 4.4.0 (Pre-release 10)
 * Fix all rope coils. (@Olink)
diff --git a/TShockAPI/GetDataHandlers.cs b/TShockAPI/GetDataHandlers.cs
index b5c9bbb0..f2083f90 100644
--- a/TShockAPI/GetDataHandlers.cs
+++ b/TShockAPI/GetDataHandlers.cs
@@ -151,9 +151,10 @@ namespace TShockAPI
 					{ PacketTypes.CrystalInvasionStart, HandleOldOnesArmy },
 					{ PacketTypes.PlayerHurtV2, HandlePlayerDamageV2 },
 					{ PacketTypes.PlayerDeathV2, HandlePlayerKillMeV2 },
+					{ PacketTypes.SyncRevengeMarker, HandleSyncRevengeMarker },
 					{ PacketTypes.FishOutNPC, HandleFishOutNPC },
 					{ PacketTypes.FoodPlatterTryPlacing, HandleFoodPlatterTryPlacing },
-					{ PacketTypes.SyncRevengeMarker, HandleSyncRevengeMarker }
+					{ PacketTypes.SyncCavernMonsterType, HandleSyncCavernMonsterType }
 				};
 		}
 
@@ -3671,6 +3672,21 @@ namespace TShockAPI
 			return false;
 		}
 
+		private static bool HandleSyncRevengeMarker(GetDataHandlerArgs args)
+		{
+			int uniqueID = args.Data.ReadInt32();
+			Vector2 location = args.Data.ReadVector2();
+			int netId = args.Data.ReadInt32();
+			float npcHpPercent = args.Data.ReadSingle();
+			int npcTypeAgainstDiscouragement = args.Data.ReadInt32(); //tfw the argument is Type Against Discouragement
+			int npcAiStyleAgainstDiscouragement = args.Data.ReadInt32(); //see ^
+			int coinsValue = args.Data.ReadInt32();
+			float baseValue = args.Data.ReadSingle();
+			bool spawnedFromStatus = args.Data.ReadBoolean();
+
+			return false;
+		}
+
 		private static bool HandleFishOutNPC(GetDataHandlerArgs args)
 		{
 			ushort tileX = args.Data.ReadUInt16();
@@ -3697,19 +3713,10 @@ namespace TShockAPI
 			return false;
 		}
 
-		private static bool HandleSyncRevengeMarker(GetDataHandlerArgs args)
+		private static bool HandleSyncCavernMonsterType(GetDataHandlerArgs args)
 		{
-			int uniqueID = args.Data.ReadInt32();
-			Vector2 location = args.Data.ReadVector2();
-			int netId = args.Data.ReadInt32();
-			float npcHpPercent = args.Data.ReadSingle();
-			int npcTypeAgainstDiscouragement = args.Data.ReadInt32(); //tfw the argument is Type Against Discouragement
-			int npcAiStyleAgainstDiscouragement = args.Data.ReadInt32(); //see ^
-			int coinsValue = args.Data.ReadInt32();
-			float baseValue = args.Data.ReadSingle();
-			bool spawnedFromStatus = args.Data.ReadBoolean();
-
-			return false;
+			TShock.Log.ConsoleDebug($"HandleSyncCavernMonsterType: Player is trying to modify NPC cavernMonsterType; this is a crafted packet! - From {args.Player.Name}");
+			return true;
 		}
 
 		public enum EditAction