A cyber attack aimed at making a service unavailable to its intended users.
Description
Denial of Service (DoS) is a type of cyber attack where the perpetrator seeks to make a computer, network, or service unavailable to its intended users. This is typically accomplished by overwhelming the target with a flood of illegitimate requests, causing legitimate requests to be dropped or delayed. A DoS attack can disrupt services, resulting in lost revenue for businesses, damage to reputation, and customer dissatisfaction. In many cases, the attacker uses a single machine to launch the attack. The more dangerous variant is Distributed Denial of Service (DDoS), where multiple compromised systems are used to target a single system, drastically increasing the attack's effectiveness. Organizations often deploy various mitigation strategies, such as rate limiting, firewalls, and specialized DDoS protection services, to prevent or minimize the impact of these attacks. Notable incidents include the 2016 Dyn attack, which disrupted major websites like Twitter and Netflix, demonstrating the potential scale and impact of DoS attacks.
Examples
- The 2016 Dyn DDoS attack affected major websites such as Twitter, Netflix, and Reddit, causing widespread outages.
- In 2020, a DoS attack targeted the Australian government, disrupting access to essential services during a crisis.
Additional Information
- DoS attacks can be executed with various methods, including SYN flood, ICMP flood, and application layer attacks.
- Organizations can implement proactive measures such as traffic analysis, redundancy, and incident response planning to reduce vulnerability to DoS attacks.