Home > Cybersecurity glossary > DDoS (distributed denial of service) 🔴 Attack

DDoS (distributed denial of service) 🔴 Attack

A DDoS attack (Distributed Denial of Service), in French a attack by denial of service distributed is a cyber attack aimed at rendering an IT service unavailable or disrupting its operation by flooding it with excessive requests from multiple sources.

  • TYPE : 🔴 Computer attack
  • DANGEROUS : 💀💀💀💀
  • FREQUENCY : 💣💣

 

How it works

  • The attacker uses a large number of infected devices (botnet) to generate a massive volume of traffic.
  • This traffic is directed to a specific target, such as a website or server.

 

  • Objective :
    • Overload the target's resources (bandwidth, CPU, memory).
    • Prevent legitimate users from accessing the service.

 

  • Common types of DDoS attack :
    • Volume attacks (e.g. UDP flood)
    • Attacks at the application layer (e.g. HTTP flood)
    • Attacks at protocol level (e.g. SYN flood)

 

  • Distinctive features :
    • Distributed nature: use of multiple attack sources
    • Difficult to block: traffic appears to come from legitimate sources
    • Scalable: can adapt quickly to countermeasures

 

💥 Consequences of a DDoS attack

  • Financial loss
  • Damage to reputation
  • Interruption of critical services
  • Vulnerability secondary attacks

 

💉 Protection and remedies

  • Real-time traffic monitoring
  • Use of firewall applications (WAF)
  • Implementation of specialised anti-DDoS solutions
  • Load sharing and automatic scaling

 

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