Telnet Service Startup and vulnerabilities (1)

The Telnet service is a standard and standard for remote logon in the network protocol. Here we will mainly explain how to install and start the Telnet service. In addition, we will introduce the vulnerabilities. Hope to help you.

To configure the Telnet service, follow these steps:

1. Install the telnet package (usually two)

1. telnet-client (or telnet). This package provides the telnet client program;

2. telnet-server. This package provides telnet server programs;

Check whether these software packages are installed before installation. The method is as follows:

 
 

  
  
[Root @ wljs root] # rpm-q telnet or [root @ wljs root] # rpm-q telnet-client
  
  
[Root @ wljs root] # rpm-q telnet-server
 
 

If no software package is detected, install it. By default, the telnet software package is installed in red hat linux 9. Generally, you only need to install the telnet-server software package.

1. Get the telnet-server-0.17-25.i386.rpm package from the installation disk of red hat linux 9.

2. install the software package

 
 

  
  
[root@wljs root]#rpm –i telnet-server-0.17-25.i386.rpm 
 
 

Ii. Start the telnet Service

1. Start the service

Method 1: Use ntsysv to add * Before telnet in the displayed window, and then press OK.

Method 2: edit/etc/xinetd. d/telnet

 
 

  
  
[root@wljs root]# vi /etc/xinetd.d/telnet 
 
 

Find disable = yes and change yes to no.

2. Activate the service

 
 

  
  
[root@wljs root]# service xinetd restart 
 
 

Iii. Test services

 
 

  
  
[Root @ wljs root] # telnet ip (or hostname)
 
 

If the configuration is correct, the system prompts you to enter the user name and password of the remote machine.

Login:

Password:

Note: Only common users are allowed by default.

4. Set the telnet port

 
 

  
  
#vi /etc/services 
 
 

Go to edit mode and find telnet (input/telnet in vi editing mode)

The following content is found: