diff --git a/VelocityCore/src/de/steamwar/velocitycore/network/handlers/PlayerSkinHandler.java b/VelocityCore/src/de/steamwar/velocitycore/network/handlers/PlayerSkinHandler.java
index f33b0b9b..ff18d309 100644
--- a/VelocityCore/src/de/steamwar/velocitycore/network/handlers/PlayerSkinHandler.java
+++ b/VelocityCore/src/de/steamwar/velocitycore/network/handlers/PlayerSkinHandler.java
@@ -54,7 +54,7 @@ public class PlayerSkinHandler extends PacketHandler {
         VelocityCore.getProxy().getEventManager().register(VelocityCore.get(), this);
     }
 
-    private Map<UUID, SkinData> skins = new LinkedHashMap<>(maxCacheSize, 1, true) {
+    private final Map<UUID, SkinData> skins = new LinkedHashMap<>(maxCacheSize, 1, true) {
         @Override
         protected boolean removeEldestEntry(Map.Entry<UUID, SkinData> eldest) {
             return size() > maxCacheSize;
@@ -64,38 +64,40 @@ public class PlayerSkinHandler extends PacketHandler {
     @Handler
     @SneakyThrows
     public void handle(PlayerSkinRequestPacket packet) {
-        if (skins.containsKey(packet.getUuid())) {
-            SkinData skinData = skins.get(packet.getUuid());
-            NetworkSender.send(((ServerMetaInfo) packet.getMetaInfos()).sender().getServer(), new PlayerSkinResponsePacket(packet.getUuid(), skinData.skin, skinData.signature));
-            return;
-        }
-
-        String url = "https://sessionserver.mojang.com/session/minecraft/profile/" + packet.getUuid().toString().replace("-", "") + "?unsigned=false";
-
-        HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
-        connection.setReadTimeout(5000);
-        connection.setConnectTimeout(5000);
-        connection.setRequestProperty("User-Agent", "SkinFetcher");
-
-        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
-            return;
-        }
-
-        InputStream is = connection.getInputStream();
-        String json = new BufferedReader(new InputStreamReader(is))
-                .lines().collect(Collectors.joining("\n"));
-
-        JsonObject obj = JsonParser.parseString(json).getAsJsonObject();
-        JsonArray properties = obj.getAsJsonArray("properties");
-        for (JsonElement propElement : properties) {
-            JsonObject prop = propElement.getAsJsonObject();
-            if (prop.get("name").getAsString().equals("textures")) {
-                String skin = prop.get("value").getAsString();
-                String signature = prop.get("signature").getAsString();
-                skins.put(packet.getUuid(), new SkinData(skin, signature));
-                NetworkSender.send(((ServerMetaInfo) packet.getMetaInfos()).sender().getServer(), new PlayerSkinResponsePacket(packet.getUuid(), skin, signature));
+        synchronized (skins) {
+            if (skins.containsKey(packet.getUuid())) {
+                SkinData skinData = skins.get(packet.getUuid());
+                NetworkSender.send(((ServerMetaInfo) packet.getMetaInfos()).sender().getServer(), new PlayerSkinResponsePacket(packet.getUuid(), skinData.skin, skinData.signature));
                 return;
             }
+
+            String url = "https://sessionserver.mojang.com/session/minecraft/profile/" + packet.getUuid().toString().replace("-", "") + "?unsigned=false";
+
+            HttpURLConnection connection = (HttpURLConnection) new URL(url).openConnection();
+            connection.setReadTimeout(5000);
+            connection.setConnectTimeout(5000);
+            connection.setRequestProperty("User-Agent", "SkinFetcher");
+
+            if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) {
+                return;
+            }
+
+            InputStream is = connection.getInputStream();
+            String json = new BufferedReader(new InputStreamReader(is))
+                    .lines().collect(Collectors.joining("\n"));
+
+            JsonObject obj = JsonParser.parseString(json).getAsJsonObject();
+            JsonArray properties = obj.getAsJsonArray("properties");
+            for (JsonElement propElement : properties) {
+                JsonObject prop = propElement.getAsJsonObject();
+                if (prop.get("name").getAsString().equals("textures")) {
+                    String skin = prop.get("value").getAsString();
+                    String signature = prop.get("signature").getAsString();
+                    skins.put(packet.getUuid(), new SkinData(skin, signature));
+                    NetworkSender.send(((ServerMetaInfo) packet.getMetaInfos()).sender().getServer(), new PlayerSkinResponsePacket(packet.getUuid(), skin, signature));
+                    return;
+                }
+            }
         }
     }
 
@@ -105,14 +107,17 @@ public class PlayerSkinHandler extends PacketHandler {
         GameProfile gameProfile = player.getGameProfile();
         GameProfile.Property property = gameProfile.getProperties().stream().filter(p -> p.getName().equals("textures")).findFirst().orElse(null);
         if (property == null) return;
-        skins.put(player.getUniqueId(), new SkinData(property.getValue(), property.getSignature()));
 
-        Set<UUID> uuidSet = skins.keySet();
-        VelocityCore.getProxy().getAllServers().forEach(server -> {
-            for (UUID uuid : uuidSet) {
-                NetworkSender.send(server, new PlayerSkinResponsePacket(uuid, property.getValue(), property.getSignature()));
-            }
-        });
+        synchronized (skins) {
+            skins.put(player.getUniqueId(), new SkinData(property.getValue(), property.getSignature()));
+
+            Set<UUID> uuidSet = skins.keySet();
+            VelocityCore.getProxy().getAllServers().forEach(server -> {
+                for (UUID uuid : uuidSet) {
+                    NetworkSender.send(server, new PlayerSkinResponsePacket(uuid, property.getValue(), property.getSignature()));
+                }
+            });
+        }
     }
 
     public record SkinData(String skin, String signature) {}