Program: 86583
Project: 86583
Buggy source:
@Override public void receiveRconMessage(Connection conn,RconMessage msg) throws IOException {
  RemoteClient client=this.clients.getClient(conn.getId());
  if (client != null) {
    String cmd=msg.getCommand();
    if (cmd != null) {
      if (cmd.startsWith("String_Node_Str")) {
        long token=this.serverContext.createToken();
        RconTokenMessage tokenMessage=new RconTokenMessage(token);
        client.setRconToken(token);
        sendRconTokenMessage(client.getId(),tokenMessage);
      }
 else       if (cmd.startsWith("String_Node_Str")) {
        client.setRconAuthenticated(false);
        client.setRconToken(ServerContext.INVALID_RCON_TOKEN);
        console.removeLogger(this.rconLoggers.get(client.getId()));
      }
 else       if (cmd.startsWith("String_Node_Str")) {
        if (!client.hasRconToken()) {
          RconMessage rconMsg=new RconMessage("String_Node_Str");
          sendRconMessage(client.getId(),rconMsg);
        }
 else {
          String password=cmd.replace("String_Node_Str","String_Node_Str");
          String serverPassword=this.serverContext.getRconPassword(client.getRconToken());
          if (serverPassword.equals(password)) {
            client.setRconAuthenticated(true);
            Logger logger=this.rconLoggers.put(client.getId(),new RconLogger(client.getId(),this));
            console.removeLogger(logger);
            console.addLogger(this.rconLoggers.get(client.getId()));
          }
 else {
            client.setRconAuthenticated(false);
            RconMessage rconMsg=new RconMessage("String_Node_Str");
            sendRconMessage(client.getId(),rconMsg);
          }
        }
      }
 else       if (client.isRconAuthenticated()) {
        console.execute(msg.getCommand());
      }
 else {
        RconMessage rconMsg=new RconMessage("String_Node_Str");
        sendRconMessage(client.getId(),rconMsg);
      }
    }
  }
}

Fixed version (ground truth):
@Override public void receiveRconMessage(Connection conn,RconMessage msg) throws IOException {
  RemoteClient client=this.clients.getClient(conn.getId());
  if (client != null) {
    String cmd=msg.getCommand();
    if (cmd != null) {
      if (cmd.startsWith("String_Node_Str")) {
        long token=this.serverContext.createToken();
        RconTokenMessage tokenMessage=new RconTokenMessage(token);
        client.setRconToken(token);
        sendRconTokenMessage(client.getId(),tokenMessage);
      }
 else       if (cmd.startsWith("String_Node_Str")) {
        client.setRconAuthenticated(false);
        client.setRconToken(ServerContext.INVALID_RCON_TOKEN);
        console.removeLogger(this.rconLoggers.get(client.getId()));
      }
 else       if (cmd.startsWith("String_Node_Str")) {
        if (!client.hasRconToken()) {
          RconMessage rconMsg=new RconMessage("String_Node_Str");
          sendRconMessage(client.getId(),rconMsg);
        }
 else {
          String password=cmd.replace("String_Node_Str","String_Node_Str");
          String serverPassword=this.serverContext.getRconPassword(client.getRconToken());
          if (serverPassword.equals(password)) {
            client.setRconAuthenticated(true);
            Logger logger=this.rconLoggers.put(client.getId(),new RconLogger(client.getId(),this));
            console.removeLogger(logger);
            if (!serverContext.getGameServer().isLocal()) {
              console.addLogger(this.rconLoggers.get(client.getId()));
            }
          }
 else {
            client.setRconAuthenticated(false);
            RconMessage rconMsg=new RconMessage("String_Node_Str");
            sendRconMessage(client.getId(),rconMsg);
          }
        }
      }
 else       if (client.isRconAuthenticated()) {
        console.execute(msg.getCommand());
      }
 else {
        RconMessage rconMsg=new RconMessage("String_Node_Str");
        sendRconMessage(client.getId(),rconMsg);
      }
    }
  }
}