Distributed Denial of Service attacks are a type of cybercrime which uses numerous systems to perform an attack, aiming to exceed a website’s capacity to handle requests and therefore prevent the website from functioning properly for online users.

Unlike a traditional Denial-of-Service (DoS) attack, which involves a single source of malicious traffic, a DDoS attack leverages multiple, often distributed, sources to flood the target, making it significantly harder to block or mitigate. DDoS attacks can incapacitate websites, applications, or entire networks by consuming all of the available bandwidth, processing power, or resources, thereby denying legitimate users access to the service or website.

The primary goal of a DDoS attack is not necessarily to infiltrate or steal data, but to make the targeted service or network unavailable, causing business disruption, financial losses, and reputational damage. DDoS attacks are increasingly common and can be executed by cybercriminals, hacktivists, or even nation-state actors with various motivations, including revenge, political activism, or extortion.

How Distributed Denial of Service (DDoS) Attacks Work

DDoS attacks are typically carried out through a botnet, which is a network of compromised devices (often referred to as “zombies”) controlled by an attacker. These devices can include computers, routers, IoT devices, and any internet-connected device with security vulnerabilities. When an attacker wants to launch a DDoS attack, they will exploit these compromised devices to send massive amounts of traffic to the target, overwhelming the system and causing it to crash or slow down significantly.

The basic mechanics of a DDoS attack are as follows:

  1. Compromising Devices: The attacker first infects thousands or millions of devices with malware, turning them into bots. These bots are often unaware of the attack, as they continue to function normally for their users while being controlled by the attacker.
  2. Coordinating the Attack: Once a botnet is established, the attacker sends a command to all the bots in the network to begin sending requests to a target’s server or network. The traffic from the bots can take many forms, including connection requests, queries, or data packets, depending on the nature of the attack.
  3. Overloading the Target: The combined traffic from the botnet overwhelms the target system’s resources, including its processing power, network bandwidth, or application-level capabilities. This causes legitimate users’ requests to either be delayed or denied entirely, as the server is too busy processing malicious traffic.
  4. Denial of Service: As the attack continues, the system or network becomes unresponsive, leading to a denial of service. In some cases, the service might experience a total shutdown, while in others, the service may simply become so slow that it is effectively unusable.

Types of Distributed Denial of Service Attacks

There are several types of DDoS attacks, each targeting different aspects of a target’s system or network. The main categories include:

  1. Volume-Based Attacks
    These attacks aim to overwhelm the target’s network bandwidth by flooding it with high volumes of traffic. Common types include:

    • UDP Flood: The attacker sends User Datagram Protocol (UDP) packets to random ports on the target machine. The target device, unable to process these packets, attempts to respond, consuming resources and leading to service degradation.
    • ICMP Flood: Also known as a Ping of Death, this attack sends large volumes of ICMP echo request packets (pings) to the target. The target becomes overloaded by the need to respond to these requests.
  2. Protocol Attacks
    Protocol attacks exploit weaknesses in the communication protocols that support the functionality of networks. These attacks can exhaust a server’s resources, such as memory or CPU. Examples include:

    • SYN Flood: This attack sends a series of SYN requests (part of the TCP handshake) to a target server. The server, in response, reserves resources in anticipation of completing the handshake but never receives the final ACK packet, leaving those resources tied up.
    • Ping of Death: A type of protocol attack where malicious packets are sent to a target system that causes the system to crash or freeze.
  3. Application Layer Attacks
    These attacks target the application layer (Layer 7) of the OSI model, which is where web servers and other services interact with end users. The goal is to exhaust the resources of the target by sending seemingly legitimate requests that require significant processing power to fulfill. Examples include:

    • HTTP Flood: The attacker sends seemingly valid HTTP requests to a web server, often exploiting vulnerabilities in the application code to consume server resources.
    • Slowloris: This attack involves keeping many connections to the target web server open and holding them open as long as possible by sending partial HTTP requests. It can exhaust the server’s connection pool and prevent legitimate users from accessing the site.

Motivations Behind Distributed Denial of Service (DDoS) Attacks

Distributed Denial of Service (DDoS) attacks are conducted for various reasons, including:

  1. Financial Gain
    Some attackers use DDoS attacks for financial extortion. They might threaten a company with a DDoS attack unless a ransom is paid to stop the attack.
  2. Political Activism
    Hacktivists often use DDoS attacks to promote political causes or to disrupt the operations of government agencies, corporations, or other entities they oppose.
  3. Competitive Advantage
    In some cases, competitors might launch DDoS attacks to cripple a rival’s service, causing downtime that affects the competitor’s revenue and reputation.
  4. Disruption and Vandalism
    Some attackers carry out DDoS attacks simply for malicious fun or to disrupt the operations of a business or government organization, without seeking any financial or political gain.

Impact of Distributed Denial of Service (DDoS) Attacks

The effects of a successful DDoS attack can be severe, especially for businesses that rely on their online presence. Common consequences include:

  • Service Downtime: The most immediate impact is service disruption, which can lead to lost business, customer dissatisfaction, and a damaged reputation.
  • Financial Loss: A prolonged DDoS attack can lead to significant financial losses due to downtime, lost sales, and recovery costs. The longer the service is down, the more it can cost an organization.
  • Resource Drain: Mitigating a DDoS attack requires considerable resources, including personnel time, additional security infrastructure, and bandwidth, which can strain an organization’s IT department.
  • Reputation Damage: If customers or users cannot access a service due to a DDoS attack, the business may suffer long-term damage to its reputation, causing users to lose trust in the organization.

Defending Against Distributed Denial of Service (DDoS) Attacks

There are several strategies for defending against DDoS attacks, including:

  1. Traffic Filtering
    Firewalls and intrusion prevention systems (IPS) can filter out malicious traffic before it reaches the target network. Techniques such as rate limiting and IP blacklisting can help mitigate large-scale traffic floods.
  2. DDoS Mitigation Services
    Specialized DDoS mitigation services, such as those offered by Cloudflare or Akamai, can absorb and mitigate DDoS attacks by dispersing the traffic across large networks, helping to keep the target service online.
  3. Scaling Infrastructure
    Cloud-based services and scalable infrastructures allow businesses to quickly scale their resources in response to increased traffic volumes, helping to handle the excess traffic caused by a DDoS attack.
  4. Redundancy and Load Balancing
    Implementing redundancy and load balancing across multiple servers and datacenters can help to distribute traffic evenly and prevent any single point of failure from being overwhelmed by the attack.

Conclusion

Distributed Denial of Service (DDos)  attacks are a serious and increasingly common threat in the digital landscape. By leveraging large networks of compromised devices, attackers can launch overwhelming traffic floods that disrupt services and cause significant financial and reputational harm.

While DDoS attacks are difficult to defend against due to their distributed nature, organizations can employ a combination of preventive measures, including traffic filtering, DDoS mitigation services, and infrastructure scaling, to help protect against these attacks and minimize their impact. As DDoS attacks continue to evolve, businesses must remain vigilant and proactive in securing their online services.

About BlackFog

BlackFog is the leader in on-device data privacy, data security and ransomware prevention. Our behavioral analysis and anti data exfiltration (ADX) technology stops hackers before they even get started. Our cyberthreat prevention software prevents ransomware, spyware, malware, phishing, unauthorized data collection and profiling and mitigates the risks associated with data breaches and insider threats. BlackFog blocks threats across mobile and desktop endpoints, protecting organizations data and privacy, and strengthening regulatory compliance.