How Hackers Are Using Backdoors To Access Networks

The word “hacker” is often associated with terrible things. So many people and businesses have suffered from their cybersecurity attacks that have been exponentially increasing. As the technology develops, they could always get their hands on more effective tools to breach into a system.

Without the proper security system, a company can be easily compromised and have all its important data stolen. Amongst those tools, hackers usually use backdoors with the purpose of accessing the networks, whether personal or business.

In this article, we’ll tell you more about how they use the backdrops to breach a system, along with the tips you can do to better protect yourself from the terrible cybersecurity risks. However, before starting much deeper into the method, did you know what backdoor actually is?

Understanding What The Backdoor Is

Yes, we’re not talking about the backdoor of your house. It’s a term used to mention malware that’s often used in hacking activities. In general, a backdoor attack is a type of malware that helps hackers access host systems without having to bypass network security and authentication requirements.

For example, a backdoor is a system that creates an alternative "entrance" to a device, network, or software so that hackers have remote access to resources such as databases and file servers.

After backdoors are installed in the network, hackers can immediately spy on the system without being detected while spreading malware throughout the network.

Unlike some cyber-attacks whose work can be easily detected (for example ransomware or osint concept in cybersecurity. It describes techniques, risks, or controls that defenders and ethical hackers must understand to protect systems and conduct authorized security testing. Learning Phishing helps you recognize attacks in the wild and apply industry-standard mitigations aligned with frameworks like OWASP and NIST.">phishing), a backdoor is a system designed to be invisible by hiding in the form of other software (disguise) such as a file converter, software update, or suggested download.

In the first place, backdoors are not installed for malicious purposes.

Backdoors of the non-criminal type are useful to help system owners who cannot access their devices due to bugs or crashes.

How Do They Work

Generally, backdoors are malware that are classified as Trojans. Trojans are malicious computer programs that pretend to be programmed to deliver malware, steal data, or open “back doors” in your system.

For example, cybercrime criminals (we assume hackers) will hide malware backdoors inside free file converters. However, the converter does not function as it should. During the converter download process, the hacker's downloader system is designed solely to open backdoors on the target system.

In other examples, hackers will hide malware backdoors in pirated Adobe software tools. Once hackers manage to enter the system through backdoors, they will switch to using rootkits.

A rootkit is a malware package designed to evade detection and hide internet activity (from the target system owner and operating system). Rootkits give hackers ongoing access to an infected system. It's like a rootkit is a "door stopper" that creates a backdoor that is a security gap that is always open.

How Hackers Install Backdoors

Backdoors not only provide hidden entrances for hackers, but they also offer a number of easier infiltration strategies. The infiltration techniques that hackers use to gain access to your device or system through a backdoor are as follows

Port binding

This technique was used before firewalls were widely used in computer network security systems. Port binding involves configuring specific information to reveal where and how messages will be transmitted and delivered within the network.

Connect-back

After firewalls began to be installed on many networks, hackers did not run out of ways by switching to using connect-back techniques. The function of this technique in running a backdoor is to connect the target system to the hacker's server system.

Connect-back also allows a reverse connection from the server to the victim platform via a port that is not protected by a firewall.

Connect Availability Use

This strategy involves using multiple malware samples to penetrate a network undetected for long periods of time. The method widens the gap for hackers to steal important and sensitive data from the target system owner.

The first malware, namely the “first-line backdoor” functions as a platform to download a second sample called the “second-line backdoor” which carries out the actual information theft.

Knowing that hackers could potentially have a lot of strategies to breach into a system, it’s advised for you to start using additional protection. One of the best ways is by using a VPN. Aside from having it as a sole program, you can also use it as an extension. Yes, it’s also better for having some Chrome VPN extension for your browser as it can effectively protect you when browsing. Thus, to get extra protection, install a VPN extension now.

What Can Hackers Do With The Installed Backdoors?

Through the development of various ways of installing backdoors by hackers, backdoors are a method that continues to develop to become more sophisticated but increasingly complex to carry out.

However, backdoors still involve attempts to break into devices, firewalls, and similar security networks. If a backdoor system is installed on the target system or network, hackers can carry out various malicious actions such as:

Ransomware

Ransomware is a type of malware designed to encrypt files while locking the target computer. It will infect devices and prevent system owners from accessing personal files unless they pay a fee. There are so many hacking cases out there that are highly related to ransomware. And when it happens to companies, it would terribly affect their finances as they need to pay a huge sum of money.

Usually, they need to pay it in bitcoin, which is already valued at millions of dollars.

DDoS Attacks

DDos or Distributed Denial of Service is a malicious attempt to disrupt and make a website or online service not respond to actual website requests.

The way DDoS works on a network due to a backdoor is to flood website traffic so that the website server goes down and you can no longer use it. Website traffic can be disrupted due to connection requests, fake packets, and incoming messages that occur continuously for some time.

spyware">Spyware

Spyware is malware that will spy on and infiltrate your system or device. It will also collect almost all forms of data, including personal information such as bank or credit account information, internet browsing habits, and usernames and passwords for important accounts.

Crypto-jacking

Another type of crime that your system could experience due to a backdoor is crypto-jacking. This type of cybercrime will hide on your computer or cellphone and then use its resources secretly to mine online currency or cryptocurrency such as Bitcoin.

How Hackers Are Using Backdoors To Access Networks

There are some methods hackers use to use the backdoors for accessing particular networks:

Using Legitimate Websites

The first method is by using legitimate websites and their CnC functions. Yes, even legitimate platforms can be used by hackers as ships to deliver malware straight to your device. This is actually considered their most efficient method as they can be more secretive as it would be hard to trace their activity, let alone their plan to attack.

The way they do it is both simple and complex. All they have to do here is use the website’s URL and use it to decipher the ciphertext and track the IP addresses that are contained within the CnC server list.

By using this masked IP address, they are basically undetected. And during this state, the would finally attack the system from the inside.

However, you might probably think that this method is kind of long and complex. While it actually is, the hackers will gain an advantage in a situation where they enter a system using a masked IP.

The next they will do is to install a remote access tool, or RAT (which acts like the animal), which can be used to obtain any personal information right from the inside. These RATs will usually install a keylogger that can capture keystrokes. They also have a different function to monitor the device and capture all the necessary data whenever the hackers need it.

“Connect-Back”

There’s also a certain method called Connect Back. It’s often used to bypass firewalls that usually act as a device protector after antivirus. The way the hackers do this method is kind of tricky.

As the incoming connections are likely blocked by the firewalls, hackers have a workaround for this, which is by using the connect-back backdoors with the intent to attack the IP address of the target system using outgoing connections.

The way they do it is by sending an email to the target, which is usually what we call as a scam email. In this email, the target is requested to input their email for various purposes (usually to claim prizes or ask for a collaboration). Once they do, that’s when the hackers would attack the target’s IP and include it inside their CnC server. From then on, they can access the system anytime they want.

Abusing Connection Availability

In this method, hackers will use two malware with different purposes. The first malware is used to infect the backdoor while also evading any kind of detection. In the process, the malware will download the second malware that will be used later to strike the jackpot.

Once a system has been infiltrated with the first malware, it’ll try to detect its whereabouts. To avoid detections, hackers would use multiple CnC servers, the more the better. After the first malware is there, it’ll download the second one. This is the malware used by the hackers to steal important data.

Another method that hackers will use is by using the common service protocol, which is manually harder to detect as they will mess with the email headers. These headers are generally harder to detect, and hackers would use this opportunity to inject their malware into the system.

What Can We Do to Protect Ourselves

From the explanation above, you already know that backdoors are dangerous malware because they are designed to be difficult or even undetectable for a long time.

Even so, there are several easy steps you can take to keep your device or system safe from backdoor attacks. Check out the steps below.

Use Antivirus

Sophisticated antivirus software can help you detect and prevent various types of malware, for example, trojans, crypto hackers, spyware, and rootkits which are often used by hackers to spread backdoor attacks.

A good antivirus includes tools and features such as WiFi monitoring, advanced firewall, web protector, and microphone and webcam privacy monitoring to ensure the security of your online activities.

With the best antivirus, you can easily detect and close backdoors before they infect your system or device.

Be careful when downloading files or software

When downloading software, files, or applications, pay attention to the availability of permission requests to install any free applications.

This is a step to anticipate the existence of PUA (Potentially Unwanted Application) or free software, files, and applications that appear safe but are actually illegal and contain malware, including backdoors.

Therefore, the easiest anticipatory step to avoid backdoors is to consider installing online security software with real-time malware detection tools.

Apart from that, always download any software, files, and applications from the official website and avoid clicking on third-party download sites for any applications.

Make use of Firewalls

Most antivirus software is equipped with a firewall that can help protect against attacks such as backdoors. Firewalls are designed to monitor all incoming and outgoing traffic on a network so that your device or system can filter out cybercrime.

For example, a firewall can tell when another user tries to access your network or device. That way, the firewall will spontaneously prevent other users from entering your system.

Firewalls can also be set to block any applications on your device that try to send your sensitive and personal data to unknown network locations.

Use Password Manager

Password managers can help you generate and save login data for all your accounts so you can log in automatically to the system. It uses the main password (master password) to encrypt your password database.

So you don't need to type your password, email, or username every time you log in. An effective strategy for preventing backdoors is to store passwords in a password manager and then create a master password.

Always update security systems

Hackers always abuse software weaknesses caused by a lack of update activity.

Fortunately, software developers often publish update features to fix vulnerabilities in software while inserting auto-update settings or providing regular update notifications. Therefore, activate the auto-update feature because it is important to keep your operating system always in the latest version.

Take advantage of Multi-Factor Authentications (MFA)

Multi-Factor Authentication (MFA) is designed to increase device or system security by preventing unauthorized resource access attempts. MFA requires you to confirm your identity in more than one way when accessing an application, website, or software.

It uses three important elements to prove your identity as the official owner, namely your password or pin, fingerprint, and even your voice. For example, when you log in to your account with a password, you will get a notification on your phone asking you to approve the request.