A2.4.2 Common Network Vulnerabilities (HL only) Notes

Distributed Denial of Service (DDoS)

1. A DDoS attack aims to overwhelm a network or service by flooding it with traffic from multiple sources.
2. Mechanism:
   1. Botnets: Attackers use networks of infected devices (botnets) to generate traffic.
   2. Target Saturation: The target becomes unresponsive to legitimate users.
3. Example:
   1. An e-commerce site is flooded with requests during a sale, causing it to crash.

Insecure Network Protocols

1. Protocols that lack encryption or authentication, making them vulnerable to interception.
2. Examples:
   1. Telnet and FTP: Transmit data in plaintext, allowing eavesdropping.
   2. HTTP: Lacks encryption, exposing sensitive information.
3. Risks:
   1. Data Interception: Attackers can capture credentials and sensitive data.
   2. Session Hijacking: Unauthorized access to active sessions.

Malware

1. Malicious software designed to damage, disrupt, or gain unauthorized access to systems.
2. Types:
   1. Ransomware: Encrypts files, demanding payment for decryption.
   2. Spyware: Collects sensitive information without user consent.
3. Example:
   1. A ransomware attack encrypts a company's files, halting operations until a ransom is paid.

Man-in-the-Middle (MitM) Attacks

1. An attacker intercepts and alters communication between two parties without their knowledge.
2. Mechanism:
   1. Eavesdropping: Capturing data as it travels between devices.
   2. Data Manipulation: Altering messages or injecting malicious content.
3. Example:
   1. An attacker intercepts a Wi-Fi connection at a café, capturing credit card information during an online purchase.

Phishing Attacks

1. Fraudulent attempts to obtain sensitive information by disguising as a trustworthy entity.
2. Mechanism:
   1. Emails or messages that appear legitimate, directing users to fake websites.
   2. Social Engineering: Exploiting human trust to extract information.
3. Example:
   1. An email pretending to be from a bank, asking users to verify their account details on a fake website.

SQL Injection

1. An attack that involves inserting malicious SQL statements into an input field to manipulate or exploit databases.
2. Mechanism:
   1. Attackers inject SQL code into user inputs, such as login forms or search boxes.
   2. This code executes on the server, allowing data extraction or modification.
3. Example:
   1. Entering ', DROP TABLE users, -- in a login form could delete a database table if input is not properly sanitized.

Cross-Site Scripting (XSS)

1. A vulnerability that allows attackers to inject malicious scripts into web content viewed by other users.
2. Mechanism:
   1. Attackers embed scripts in user-generated content, such as comments or forums.
   2. When other users view the content, the script executes in their browsers.
3. Example:
   1. A blog comment contains a script that steals cookies from other users, allowing session hijacking.

Unpatched Software

1. Software that has not been updated with the latest security patches, making it vulnerable to exploitation.
2. Risks:
   1. Known Vulnerabilities: Attackers can exploit documented weaknesses.
   2. Increased Attack Surface: Outdated software provides entry points for malware and attacks.
3. Example:
   1. An operating system that has not been updated, allowing attackers to exploit a known vulnerability.

Weak Authentication

1. Security measures that are easy to bypass or crack, often due to simple passwords or lack of multifactor authentication.
2. Risks:
   1. Brute Force Attacks: Attackers can guess passwords using automated tools.
   2. Credential Theft: Weak passwords are easily compromised.
3. Example:
   1. A website that only requires a username and a simple password, without any additional verification.

Zero-Day Exploits

1. Attacks that exploit previously unknown vulnerabilities in software or hardware before a patch is available.
2. Mechanism:
   1. Attackers discover a vulnerability and develop an exploit before the vendor is aware.
   2. These attacks are highly effective because there are no defenses in place.
3. Example:
   1. An attacker discovers a flaw in a popular browser and spreads malware before the issue is publicly known and patched.