Cyber Health

Denial of Service Attacks

A Denial of Service (DoS) attack is a type of cyber-attack that attempts to make a website, online service or computer network unavailable by overwhelming it with a flood of traffic or requests, causing it to crash or become extremely slow and unresponsive.. It can be targeted at a single system or an entire network, and can range from minor disruption or slowness to a complete shut down.  


DoS attacks can be extremely disruptive to businesses, and there have been several high-profile (DoS) attacks that have targeted manufacturing companies in recent years:

  1. In February 2021, a major manufacturer of industrial control systems was targeted by a sophisticated DoS attack that caused severe disruption and prevented the company from conducting operations.
  2. In June 2020, Honda experienced a DoS attack that disrupted its global operations. The attack forced the company to temporarily shut down some of its manufacturing plants, and impacted its ability to access email and other internal systems.
  3. In June 2017, Mondelez International, a multinational food and beverage company, was hit by a massive cyber attack that disrupted its operations worldwide. The attack included a DoS component, which prevented employees from accessing critical systems and data.

To prevent a DoS attack, it is important to take the following steps:

  1. Implement network security devices and tools such as firewalls, intrusion detection and prevention systems, and load balancers to help detect and block DoS traffic
  2. Secure your systems using strong passwords and access controls
  3. Configure your network infrastructure to filter out traffic from suspicious or malicious sources. This can be done using access control lists (ACLs), routers, and firewalls.
  4. Use content delivery networks (CDNs) to distribute web traffic across multiple servers, making it harder for attackers to target a single server or resource
  5. Regularly update your systems and software with the latest security patches and updates to protect against known vulnerabilities
  6. Monitor your network activity regularly to help detect suspicious activity before it becomes a serious threat

If a DoS attack is already in progress, you can try the following:

  1. Block the source IP address(es) that are sending malicious traffic, as well as quickly notify your ISP in order to mitigate the damage.  They may be able to help mitigate the attack by filtering out malicious traffic
  2. Use a DDoS mitigation service like Cloudflare to help block the malicious traffic and keep your website or network operational during an attack
  3. Disable non-essential services: If you can identify the specific service being targeted, you may be able to mitigate the attack by disabling it temporarily
  4. Temporarily increase your network bandwidth to keep services available during the attack
  5. Implement rate limiting policies that limit the number of requests that can be made to systems in order to prevent attackers from overwhelming your services with malicious traffic


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