What is DoS
Denial-of-service, commonly known as DoS attacks, refers to cyber threats that are generally done to crash a website by throwing in large volumes of traffic from a particular source. Once that is done, it gets easier for the intruder or hacker to make their way into your PC and your home network and access all your private and important information. When you have a firewall installed, it blocks out DoS threats by keeping a close check on the volume of traffic generated from the potential threat and immediately blocking it out. The firewall also looks out for spoof attacks where the hacker attempts to enter your network disguised as a trusted source in order to gain access to your network.
There are a lot of high-profile DoS attacks where a lot of DoS attacking systems attack a particular company or individual’s website at one go. In such an attack, the website and servers crash immediately and the website is taking over by hackers. Such attacks get extremely difficult to detect as well as a treat because there are multiple sources of DoS attacks and malware with high volumes of traffic. Ordinary antivirus and PC firewalls cannot protect the system from such attacks, which is why a heavy-duty firewall software is needed for bigger organizations. In a lot of cases, the hackers who conduct DoS attacks get all your personal and company’s extremely confidential information and threaten to leak if they don’t get the ransom.
Types of DoS attacks
There are various types of DoS attacks that attack operating systems and private networks:
Amplified DNS DoS Attack
In this, a crafted domain name system (DNS) request is generated by the intruder, which appears to have originated in the victim’s personal and private PC network. This sends the victim to the misconfigured DNS servers that are usually operated and managed by the intruders. When the intermediate DNS servers respond to the fake DNS requests, the amplification occurs. This causes higher volumes of data traffic than ordinary DNS responses, resulting in denying legitimate users of the network any access to the network and service. Fake traffic is generated to the servers especially the DNS servers and HTTP servers by the application layer. Some application servers also mess up the entire server making it extremely weak and vulnerable to future potential threats and DoS attacks.
Buffer overflow DoS Attack
Here, the attacker sends extremely high volumes of traffic than was ever anticipated by the website and server developers. These types of attacks can be email attachments with extremely heavy attachments or 256-character file names, which crashes the applications.
Ping of death
Here, the PING protocol is abused by sending high volumes of request messages with oversized payloads. This causes the attacked systems to crash because of the overwhelming requests and PINGs which affects the overall functioning of the PC.
In order to safeguard your network and your PC, invest in a heavy-duty firewall software to ensure you don’t face any issues with hacking or with DoS attacks in the future.
What are the adverse effects of DoS attacks?
DoS attacks don’t just slowdown of the PC performance, they can cause multiple problems to the system. Moreover, some of the common problems experienced by operators are listed below:
● Inaccessible service
● Ineffective service
● Interrupted network traffic
● Interference of connection
How to prevent a DoS attack?
Some of the preventive measures offered by CERT/CC are as follows:
● Install router filters for checking the risk of DoS attacks
● Install patches for protecting against TCP SYN flooding, if possible
● Disable unnecessary network services
● Try and enable quota system for the operating system
● Routine verification of physical security
● Use tools like Tripwire for safety
● Opt for fault-tolerant networking configuration
● Maintain backup policies and schedules every day
● Maintain strong password policies that are hard to break
