Computer/network backdoors are potential gateways for hackers to access networks by bypassing normal/minimum security measures that can be in place. Once criminals have gotten into the system they can steal personal information, install malware, or even hijack devices. Backdoors can also help people who may have been locked out of devices/networks or can even be used just for solving software issues.
Different from other methods, backdoors are silent and don’t involve things such as text messages to execute. Backdoors are also persistent. This means that hackers can repeatedly use them as long as they are there. Backdoors are classified as Trojans and similar to the Ancient Greek Trojan Horse, they conceal surprises. Trojans can be found in many forms such as files to download or email attachments and can deliver many malware threats. Trojans can also sometimes execute worm-like functions, replicating and spreading through different devices without further instructions from hackers. This can lead to more and more devices being infected allowing hackers to access to many more devices.
Once hackers set up a backdoor they can do many things such as
- Spyware
This is malware that once deployed on your system will track and collect information. Any downloads made, files opened, passwords, and usernames can be tracked and collected. Some spyware will also track keystrokes and clicks made
- Cryptojacking
This malware is designed so that the victim’s computer is used for mining cryptocurrency. Hackers have found out that instead of purchasing the expensive equipment needed for mining cryptocurrency they can just exploit other people’s computers and use those instead.
- Ransomware
This malware will often encrypt files and lock the victim’s computer. In order to take back precious documents, the victim will have to pay the hackers. Payment could be in the forms of cryptocurrency such as Bitcoin.
- Botnets
Hackers can gain high-level access to a system taking control over it remotely. They can then add it to a mainstream network full of hacked systems (botnet). With all these zombie computers under the control of the hacker, the hacker can simultaneously tell all the computers to overwhelm a website/network. The flood of traffic prevents the website/network from distinguishing real requests from fake ones. This will ultimately shut down or crash the website/network.
There are some ways you can take to prevent hackers from opening up backdoors or inserting trojans. Multi-factor authentication can stop hackers from using passwords repeatedly across platforms. By monitoring network activity, any unusual data spikes happening could mean someone has a backdoor. To stop/prevent this firewalls will track inbound and outbound activity. Lastly, any decent anti-malware solution should be pretty effective at stopping criminals from deploying trojans or any rootkits.
Source: MalwareBytes