Question

Consider a company that has an intrusion detection system in half of its systems (50%), has bring your own device (BYOD) for 30% of its employees, and uses three systems (computers 40%, smartphones 25%, and cloud 35%).

The probability of a breach is 11%.

The probability of a breach given there is an intrusion detection is 15%

The probability of a breach given there is no intrusion detection 25%

The probability of a breach given employees’ use their own devices 43%

The probability of a breach given employees use company devices 13%

The probability of a breach given computer systems is 7%

The probability of a breach given smartphone systems is 27%

The probability of a breach given cloud system is 17%

3.a. What is the probability of a breach of company computer systems that have no intrusion detection?

3.b. What are the conditions that result in the highest risk of an attack?

Answer 1

1) The probability of a breach given employees use company devices 13% or 13\100

The probability of a breach given computer systems is 7% or 7\100

The probability of a breach given there is no intrusion detection 25% or 25\100

Therefore we can say that probability of a breach of company computer systems that have no intrusion detection= 13\100* 7\100*25\100

=2275\1000000

=91\40000

2) Conditions that result in the highest risk of an attack are:-

• Using personal device
• Using public network.
• Clicking on any unauthenticated url.
• Sharing any personal details
• Downloading software from an unauthenticated site.

Common types of cyber attacks:

• Malware

  Malware is a term used to describe malicious software, including spyware, ransomware, viruses, and worms. Malware breaches a network through a vulnerability, typically when a user clicks a dangerous link or email attachment that then installs risky software.

• Phishing

  Phishing is the practice of sending fraudulent communications that appear to come from a reputable source, usually through email. The goal is to steal sensitive data like credit card and login information or to install malware on the victim’s machine

• Man-in-the-middle attack

  Man-in-the-middle (MitM) attacks, also known as eavesdropping attacks, occur when attackers insert themselves into a two-party transaction. Once the attackers interrupt the traffic, they can filter and steal data.

• Denial-of-service attack

  A denial-of-service attack floods systems, servers, or networks with traffic to exhaust resources and bandwidth. As a result, the system is unable to fulfill legitimate requests. Attackers can also use multiple compromised devices to launch this attack. This is known as a distributed-denial-of-service (DDoS) attack.