From 3644ad9d70b52f877ce6a89ed61b23a4116f26ed Mon Sep 17 00:00:00 2001
From: Jesse Boyd <jessepaleg@gmail.com>
Date: Wed, 7 Mar 2018 15:00:11 +1100
Subject: [PATCH] Ignore CUI connections with more than 3 failed attempts.

---
 .../java/com/sk89q/worldedit/LocalSession.java   | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/core/src/main/java/com/sk89q/worldedit/LocalSession.java b/core/src/main/java/com/sk89q/worldedit/LocalSession.java
index fdeb0997..4e04d5b9 100644
--- a/core/src/main/java/com/sk89q/worldedit/LocalSession.java
+++ b/core/src/main/java/com/sk89q/worldedit/LocalSession.java
@@ -96,6 +96,7 @@ public class LocalSession {
     // Non-session related fields
     private transient LocalConfiguration config;
     private transient final AtomicBoolean dirty = new AtomicBoolean();
+    private transient int failedCuiAttempts = 0;
 
     // Session related
     private transient RegionSelector selector = new CuboidRegionSelector();
@@ -1202,14 +1203,25 @@ public class LocalSession {
      */
     public void handleCUIInitializationMessage(String text) {
         checkNotNull(text);
+        if (this.failedCuiAttempts > 3) {
+            return;
+        }
 
-        String[] split = text.split("\\|");
+        String[] split = text.split("\\|", 2);
         if (split.length > 1 && split[0].equalsIgnoreCase("v")) { // enough fields and right message
+            if (split[1].length() > 4) {
+                this.failedCuiAttempts++;
+                return;
+            }
             setCUISupport(true);
             try {
                 setCUIVersion(Integer.parseInt(split[1]));
             } catch (NumberFormatException e) {
-                WorldEdit.logger.warning("Error while reading CUI init message: " + e.getMessage());
+                String msg = e.getMessage();
+                if (msg != null && msg.length() > 256) msg = msg.substring(0, 256);
+                this.failedCuiAttempts++;
+                WorldEdit.logger.warning("Error while reading CUI init message: " + msg);
+
             }
         }
     }