Question

Exercises 28-55 are problems or shortanswer questions. Describe how a Trojan horse attacks a computer system.

Short answer

A Trojan horse is deceptive malware that allows unauthorized access to a system, often delivered through disguised files.

Step-by-step solution

Define a Trojan Horse

A Trojan horse is a type of malicious software that pretends to perform a desirable function but instead allows unauthorized access to the user's computer system when executed.

Initial Infection Strategy

A Trojan horse typically gets into a system through deceptive means like a seemingly legitimate email attachment, a fake program, or disguised software that the user downloads and installs.

Activation of Malicious Code

Once inside the system, the Trojan horse activates its malicious code, which could open a backdoor for the attacker, steal data, or introduce other harmful activities.

Execution of the Attack

After activation, the Trojan can allow attackers to monitor user activities, record passwords, delete files, or gain control over the system, depending on its design.

Covering its Tracks

Many Trojans attempt to hide their presence by disabling antivirus software and making it difficult for users to detect them on the system.

Key concepts

Malware

Malware, short for malicious software, is a broad term that encompasses any software designed to cause harm to a computer system. Trojans are a specific type of malware that trick users into downloading and executing them by masquerading as legitimate programs. Once inside a system, malware can perform a myriad of harmful actions, including stealing personal information or damaging files.

There are several types of malware, such as:

• Viruses: These attach themselves to legitimate files and spread as those files are shared.
• Worms: These do not need to attach to anything and can replicate themselves across systems.
• Ransomware: This encrypts the victim’s data and demands payment for the decryption key.
• Spyware: This tracks user activity and gathers information about them without their knowledge.

Understanding malware is crucial for protecting personal and organizational data from potential threats.

Computer Security

Computer security is the practice of protecting computer systems and networks from digital threats, such as malware, that could cause data breaches or other forms of cyber damage. Ensuring computer security involves employing a mix of strategies and technologies to safeguard systems.

Key aspects of computer security include:

• Encryption: Protecting data through encoding, making unauthorized access impossible without a decryption key.
• Firewalls: Blocking unauthorized access while permitting outward communication.
• Antivirus Software: Detecting and removing malicious software from systems.
• User Authentication: Implementing secure ways to verify the identity of users, such as passwords and biometric scans.

This holistic approach helps in preventing unauthorized access and ensuring the integrity and confidentiality of sensitive information.

Cyber Attack

A cyber attack is a deliberate attempt by an individual or group to breach the information system of another individual or organization. Such attacks utilize different methods, including deploying malware like Trojan horses, to exploit vulnerabilities.

Forms of cyber attacks include:

• Phishing: Using deceptive emails or websites to trick users into providing sensitive information.
• Denial of Service (DoS): Flooding a network or server with traffic to make it unavailable.
• Man-in-the-Middle (MitM): Intercepting communications between two parties to steal or alter information.
• SQL Injection: Inserting malicious code into a database query to gain unauthorized access.

Cyber attacks are becoming increasingly sophisticated, with attackers often seeking financial gain, data theft, or simply causing havoc to disrupt normal operations.

Unauthorized Access

Unauthorized access refers to gaining entry into a computer, network, or data system without permission. This is often a central objective for many cyber attacks, including those facilitated by a Trojan horse. Unauthorized access can lead to severe consequences, including data breaches and identity theft.

Common ways through which unauthorized access is gained include:

• Exploiting weak or stolen passwords to log in to accounts illegally.
• Phishing, where attackers pose as trusted entities to gather login credentials.
• Exploiting software vulnerabilities to bypass security measures without user knowledge.

To guard against unauthorized access, it is crucial to regularly update passwords, educate users on recognizing phishing attempts, and maintain updated security software. Prevention and awareness are key in making systems resilient against unauthorized intrusions.