Ticket #263: You need READ to be able to connect to a group.

extensions/guacamole-auth-mysql/src/main/java/net/sourceforge/guacamole/net/auth/mysql/MySQLConnectionGroup.java

@@ -177,6 +177,11 @@ public class MySQLConnectionGroup extends AbstractConnectionGroup {
         permissionCheckService.verifyConnectionGroupUsageAccess
                 (this.connectionGroupID, this.userID, MySQLConstants.CONNECTION_GROUP_BALANCING);
 
+        // Verify permission to delete
+        permissionCheckService.verifyConnectionGroupAccess(this.userID,
+                this.connectionGroupID,
+                MySQLConstants.CONNECTION_GROUP_READ);
+        
         return connectionGroupService.connect(this, info, userID);
     }