Backdoor in hacking

A backdoor can refer to a legitimate point of access embedded in a system or software program for remote administration. Generally a programmer may sometimes install a back door so that the program can be accessed for troubleshooting or other purposes. However, attackers often use back doors that they detect or install themselves, as part of an exploit.

Some administrative backdoors are protected with a hardcoded username and password that cannot be changed; though some use credentials that can be altered. Often, the backdoor's existence is unknown to the system owner and is known only to the software maker. Built-in administrative backdoors create a vulnerability in the software or system that intruders can use to gain access to a system or data.

Attackers also can install their own backdoor on a targeted system. Doing so allows them to come and go as they please and gives them remote access to the system. Malware installed on systems for this purpose is often called a remote access Trojan, or a RAT, and can be used to install other malware on the system or exfiltrate data.

Backdoor threats increase when multiuser and networking operating systems are used by many organizations. In a login system, a backdoor used for system access may be in the form of a hard-coded username and password.

A network administrator may intentionally create or install a backdoor program for troubleshooting or other official use. Hackers use backdoors to install malicious software files or programs, modify code or detect files and gain system and/or data access. Even backdoors installed by network administrators pose security risks because they provide a mechanism by which the system can be exploited if discovered.