What is a denial-of-service vulnerability?

A DoS attack is a malicious attempt to render a machine or network inaccessible to its intended users by hampering the device’s normal functionality. Malicious actors launch these attacks by sending information and unusual traffic or other hazardous activity that triggers a system crash.

In addition to manipulating network packets, malicious actors may exploit logical, programming, or resource-handling vulnerabilities to render services unavailable for valid users.

Perpetrators of DoS attacks often target high-profile institutions such as government agencies, trade organizations, banks, media, and manufacturing organizations and exploit denial-of-service vulnerabilities with the intent to overwhelm their systems and cause disruption.

Here’s how different types of DoS attacks work:

Buffer overflow attacks

Buffers are temporary storage regions during data transfer. A buffer overflow occurs when the data to be transferred exceeds the available memory. This denial-of-service vulnerability can cause a machine to exhaust the capacity of available memory, hard disks, and CPU time. Buffer overflow attacks often lead to system crashes, sluggish behavior, and other abnormal server behaviors, resulting in a denial of service.

Flood attacks

In this attack, cyberattackers oversaturate server capacity with an overwhelming amount of packets (the basic unit of communication over a network), flooding the target system and causing a denial of service. For a successful DoS flood attack, the attacker needs more bandwidth capacity than the target system.

Distributed denial of service (DDoS) attack

Malicious actors use multiple systems to orchestrate a synchronized attack on a single target. The significant difference is that while DoS attacks often originate from one single computer, DDoS attacks come from multiple systems and locations.

Differentiating between a general issue — such as heavy bandwidth consumption or poor network connectivity — and a DoS attack can be challenging.

Here are indicators of compromise that suggest a denial of service vulnerability has led to an attack:

• All devices on a given network lose connectivity abruptly.
• Specific components of a website, such as a web property, are unable to load.
• Slow network performance, such as long website load times.

Vulnerability management is crucial to identifying risks and attack surfaces that threat actors can exploit. With the Armis Platform, you can assess vulnerabilities, prioritize which ones pose the biggest risk to your business, minimize the risk of a denial-of-service attack, and strengthen your security posture.