What is a Botnet?

Botnet is a program installed on a computer that then, being controlled remotely, uses the host device to perform certain actions on the Internet. Of course, such a program is malicious. It is introduced into the device unbeknownst to the user, acts in secret, and the work it performs is illegal.

A botnet is a network of devices on which a botnet is installed and running. Such a network is constantly growing but continues to be controlled from one center, like a flock of sheep. It’s no wonder the command and control center of such a network is called a “herder.” A botnet is a growing controllable crowd that can be given different tasks and provided with the necessary software to complete them.

Botnets are a new word in hacking since one hacker with a botnet is already an army that makes it possible to take advantage of those system vulnerabilities that appear only under a large number of requests from different sources.

How Botnets Work: Algorithms

• Email spam. Spam can have different purposes. It can be real advertising or fraud messages, and it can also be the distribution of malware. A properly configured botnet can send tens of billions of messages per day. In addition, email spam is a way for new machines to join the botnet.
• Comments – a botnet can be used to rain down comments to keep a post trending or to support one or another political opinion in society. Such bots can track, for example, YouTube videos with certain names and leave pre-written comments under them.
• DDoS (Distributed Denial of Service) attacks are massive raids by bots with requests to the server, which crashes due to overload and cannot respond to requests. Such an attack is impossible for a single hacker but possible for a botnet. DDoS attacks are usually carried out against government systems and economic or political competitors.

For example, from the latest news, Ukraine was hit by DDoS attacks from hacked WordPress sites.

• Hacking² and stealing money from accounts can also be carried out using vulnerabilities exploited by botnets. Certain financial breach mechanisms allow bot-driven thefts on a huge scale. Also, targeted hacking can be carried out with the help of a powerful influx of requests, exposing the flaws in the defenses of the attacked systems.

How do Botnets Infect a Computer?

A botnet penetrates a computer according to a scenario familiar from examples of other malicious programs. Most likely, the user inadvertently opens a file attached to a spam email or clicks on that can be received both by email and in any messenger app. If so, the botnet will most likely be downloaded and installed via scripts embedded in a file or website. 

Once the botnet is deployed, it establishes contact with the control and command center and waits for the task. What is especially interesting about bots is that they are universal in their functions. As far as their permission allows, they can perform completely different actions. The botnet can be reprogrammed Signs Your Computer Is Part Of A Botnet

Signs of becoming a part of a botnet may be the consequences of other malware’s presence, hardware problems, lack of free memory, and whatnot. However, pay attention to these occurrences, especially if you register more than one of them:<

• Your computer struggles when it should idle. You can hear its fans rotate intensely, and the processor sounds like it is busy. You might want to check the Task Manager for strange processes. 
• Internet connection might seem to worsen. Nothing is wrong with the bandwidth, but the botnet might be generating dense traffic that interferes with what you are trying to do.
• The shutdown of your device might become considerably longer than usual. As if during the system update. 
• Crashes and freezings of the programs that previously worked fine can signify malicious botnet activity. Check the process that consumes a lot of your RAM. 
• Other people may complain that your mailbox or social media account distributes suspicious messages. That would be a certain hint that you are in a botnet. 

How Can a Computer be Protected from Botnet?

• First, you should have a good antivirus program. We recommend GridinSoft Anti-Malware. It is cost-effective, quick, and highly efficient. It protects you from suspicious and dangerous sites while you surf, and it also instantly removes malware if it has somehow penetrated your computer. If you have already managed to infect your computer with a bot, perform a deep scan using Anti-Malware. The bot will be found and removed.
• Take care of your passwords. On all devices where they can be set up – choose strong passwords. Pay special attention to routers and use public Wi-Fi. Remember to change your password from time to time. The password must include uppercase and lowercase letters, numbers, and special characters.
• And, of course, be extremely careful when it comes to unexpected emails and messages on social networks or instant messengers. Do not download attachments or click on links contained in these messages. If you do not know the author and do not understand why the letter came to you, delete it immediately. Spam of this kind is the most common way to distribute malware.

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Why do PCs reboot without any reason?

There are plenty of reasons for PC unpredictable restarting. All of them are pretty serious, so solving them is likely essential to save your computer and your data. To understand which problem is yours, you need to check each possible case until you find one that is yours. To make the process structured, we will divide it into two parts – hardware and software-related checks.

Hardware-related problems

These things are the most dangerous. While software issues usually do not affect file safety, hardware ones do. It is essential to figure out the problem properly and deal with it as soon as possible.

Power issues

One of the most widespread reasons for the sudden PC rebooting is power supply problems. It may be damaged, worn, or overloaded, but the effect is simple: some of your hardware parts do not receive enough power and then shut down, causing the PC to reboot. To figure out if that is the case, use online services that allow you to calculate the power your computer consumes¹. Then, you can compare the number with your power supply max power emitted. If the power supply can emit less power than your PC can consume, the problem is right there.

Damage or wear of the power supply is harder to detect. Only the serious damage to this PC part can be seen: an outbalanced cooling fan, damaged cables, and so on. It may be even worse, but in worse cases, you will not be able to start your computer. Bring your power supply to the service if you managed to do all the next checkups and did not fix the problem.

Overheating

The era of “cold” CPUs passed long ago. Now, only ARM-based chips used in smartphones and some other mobile devices can be cooled passively – without fans, heat sinks, etc. Computer hardware, on the other hand, can heat up significantly. Problems appear when you use a compact system unit or a laptop. Both of them tend to have problems with heat sinking, especially when the hardware is working at high temperatures. You may check the current temperature of your hardware elements in Task Manager and third-party apps that can check the data hardware sensors. Normal temperature for CPU/GPU while running something heavy is ~70-80°C². Lower is better. Higher is not.

The reasons for overheating are different. Generally, if you did not install any new hardware but discovered that your computer is overheating, it is a good idea to open the system unit and clean the detail up from the dust. It is a perfect habit to clean your computer at least once a quarter – just like washing your car. If you have changed your hardware, and the problem appeared, you will need to update your heat sinks. In some cases, you may even need a water cooling system.

Overclocking

That is a case that touches on both overheating and power issues. Overclocking is a process of increasing the CPU clock rate by increasing the bus multiplier. Most modern Intel processors do not offer such an ability – only ones with K/KF letters in their index. On the other hand, AMD CPUs can easily be clocked regardless of the model (at least, the vast majority of them). Not only may the processor be overclocked – but GPU power can also be increased in such a way. But the negative effects are pretty much the same

Overclocking causes an increased power consumption and increased heating. The correlation between power use and clock rates is not linear: it is rather similar to parabolic graphs. Generated heat, however, is strictly related to power usage. Nevertheless, an overclocked PC may suffer from both power issues and overheating. Try to decrease the clock rate – it will likely help you.

Disk issues

It is a rare source of a problem, but it still can appear, especially if you use HDD. In contrast to SSD, HDD can die slowly, getting one bad sector after another. One time, the bad sector can appear in the cell where some crucial system info is stored. When the system tries to get this info and fails, it may trigger rebooting. However, a much more common case in that situation for modern computers is BSOD.

To prevent any issues with your HDD, check it with disk scanning tools. The scanning process takes about 1.5-2 hours, and it is recommended not to use your computer during the scan. You will be able to see the problematic sectors on your disk, along with ones already bad or inaccessible.

Software-related reasons for PC rebooting

In a positive case, the reason for constantly rebooting a PC is related to the software you have on your computer. Most of these reasons cannot even be called a problem – it is just an unregulated need. However, there is still a way to fix that.

System updates

Operating systems nowadays receive weekly updates. Windows has a regular updating schedule: at least 2 minor updates during the month and a cumulative update every quarter. Moreover, half-yearly patches may bring new functionality to the OS. Sometimes, when you do not update your PC for a long time or have reinstalled Windows from an old image, you may get into a situation where the system tries to install all possible updates. And most of these patches require rebooting.

It is recommended to wait until the system receives all the required updates. They are released not just to annoy you. Important bug fixes, closing security breaches, new functions – all these things are vital. But when you need to access your PC here and now and have no time to wait – schedule the installation of the update or temporarily disable them.

Third-party software updates or other actions

Same as the OS, third-party programs may also require the reboot of your PC. Oftentimes, they offer the user the choice – to reboot now or later. But there are rare cases when they have a timer on rebooting or do not give you a choice. In that case, try to install all updates and control the installation manually – to be sure that you don’t miss any windows³.

Malware-related issues

Rarely, malicious programs may cause your computer to reboot. In some cases, these reboots are caused by the extremely high CPU/GPU load. Such a load may happen when you are infected with coin miner viruses. But most of the viruses spread nowadays do not have such side effects. They are concentrating on making money on you, this or another way. And making such disruptions in this “farming” is not the best solution.

I hope that this guide will help you to resolve the problem you have. For sure, I cannot describe all the particular cases that may cause the PC rebooting problem. But this guide represents all common cases that will likely solve the problem you have.

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