Over the course of the 21st century, technology and our dependence on it has grown exponentially. Almost all of our data, including documents and photos, are stored on our laptops and smartphones. Alongwith this, the vulnerability of our data has also increased, and hackers are finding newer ways to breach your network and steal or exploit data.
One of these lesser-known methods is known as banner grabbing, and in this article, we shall divulge all the facts you need to know about it and also how you can protect yourself against such attacks.
Banner grabbing is essentially a practice that is used to obtain information about services that are being run on a remote computer or client. This method is generally implemented by administrators while inventorying their systems or ethical hackers to run penetration tests to expose any vulnerabilities in a network.
Banners are the welcome screens that provide software version numbers and other system information on network hosts, and this makes it an ideal route for malicious hackers to use and obtain information about the services running on the system.
How is a banner grabbing attack carried out?
The technique involves using services such as Telnet, or a proprietary program, to establish a connection with a remote machine, after which a compromising request is sent. That, in turn, will cause a vulnerable host to respond back with a banner message, which could contain information that the hacker could use to compromise the system further.
The banner for a Hypertext Transfer Protocol (HTTP) service, for example, will typically show the type of server software, version number, when it was modified last, and other similar information. If a hacker gets hold of this information, they can find potential flaws and attack the system even further.
How do you protect yourself?
There are a few ways you can try and minimise the chances of a banner attack on your system. The first thing you can do is to disable any unused services on your system that could provide any potential banner information.
The next thing you can do is configure your the network host’s application or operating system to either disable the banners or remove information from the banners, that an attacker could misuse.
And the last thing that could possibly prove effective or prevent attackers from exploiting your system is to customise your banners to show a warning message. This wouldn’t really stop an attack from happening but will give a clear message to any attacker that the system is under scrutiny and is monitored, and could thus stop the attack from happening further