Attacks on availability are cyberattacks designed to shut systems down and block legitimate users from accessing important services. These attacks can be hugely disruptive, expensive, and dangerous for organizations. My bottom-line is that availability attacks are becoming more powerful every year, and strong defenses are now a necessity, not an option
What Is an Attack on Availability?
An attack on availability targets one of the key pillars of cybersecurity by disrupting access to systems, networks, or data. When availability is attacked, legitimate users cannot reach the services they depend on. This includes websites, apps, financial systems, hospitals, and even government platforms. These attacks don’t always steal data their power comes from shutting everything down and causing chaos.
Hyper Volumetric DDoS Attacks
One of the clearest examples of an availability attack is a Distributed Denial-of-Service (DDoS) attack. In September 2025, Cloudflare reported blocking a record-breaking 11.5 Tbps
DDoS flood, one of the largest ever recorded. Attackers used thousands of compromised devices to overwhelm the target with traffic, making the service unreachable to real users. These attacks are increasing in size and frequency every year, proving how serious this threat is (Dark Reading, 2025).
Impact on Organizations and Users
When availability collapses, everything from customer service to financial transactions can shut down. Businesses lose money, users lose trust, and essential services like healthcare or emergency communication can be completely disrupted. These attacks expose how dependent we are on technology and how vulnerable organizations can be without strong mitigation strategies.
Conclusion
Attacks on availability are growing more aggressively and more common. They not only interrupt daily operations but can also cause long-term damage to organizations and the people who rely on their services. Understanding these attacks is the first step in building stronger defenses.
References
Cloudflare. (2025). DDoS threat report. https://www.cloudflare.com
Dark Reading. (2025). Cloudflare blocks record-breaking 11.5 Tbps DDoS attack. https://www.darkreading.com