Network Infrastructure & Security Weaknesses Flashcards

What is the role of a firewall in network infrastructure?

Answer: Block unauthorized access while permitting legitimate communication

A firewall acts as a security barrier, monitoring and controlling incoming and outgoing network traffic based on predetermined security rules. Its primary role is to establish a robust defense between a trusted internal network and untrusted external networks, like the internet. By filtering traffic, firewalls prevent unauthorized access and malicious activities while ensuring legitimate data flow for business operations.

Which device connects multiple networks together?

Answer: Router

A router is a network device that forwards data packets between different computer networks. It operates at Layer 3 (the network layer) of the OSI model, using IP addresses to determine the best path for data transmission. Routers are essential for connecting local area networks (LANs) to wide area networks (WANs), such as the internet, enabling communication across disparate network segments.

What is a common weakness found in wireless networks?

Answer: Weak or default passwords

A common and significant weakness in wireless networks is the use of weak, easily guessable, or default passwords. Many devices come with factory-set default credentials that are publicly known, or users choose simple passwords for convenience. Attackers can easily exploit these to gain unauthorized access to the network, compromising data and potentially launching further attacks.

What can an open port on a network indicate?

Answer: Potential security risk

An open port on a network device indicates that a service is listening for incoming connections on that specific port. While some open ports are necessary for legitimate services to function, an unnecessary or misconfigured open port can expose a system to potential attacks. Attackers can exploit these open ports to gain unauthorized access, inject malware, or launch denial-of-service attacks, making them a significant security risk.

What is the purpose of network segmentation?

Answer: Enhance security by isolating segments

Network segmentation involves dividing a computer network into multiple smaller, isolated subnetworks or segments. The primary purpose is to enhance security by creating boundaries that restrict the lateral movement of threats. If one segment is compromised, the attack is contained, preventing it from spreading to other critical parts of the network, thereby reducing the overall attack surface and improving control over traffic flow.

Which protocol is insecure and should be avoided when possible?

Answer: Telnet

Telnet is an application protocol used to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. However, Telnet transmits all data, including usernames and passwords, in plain text without any encryption. This makes it highly insecure and vulnerable to eavesdropping and man-in-the-middle attacks, which is why secure alternatives like SSH (Secure Shell) should always be used instead.

What is network sniffing?

Answer: Capturing and analyzing network traffic

Network sniffing, also known as packet sniffing, is the process of intercepting and logging traffic passing over a digital network or part of a network. This technique involves using specialized software or hardware to capture data packets as they travel across the network. While it can be used for legitimate network monitoring and troubleshooting, it is also a common method used by attackers to eavesdrop on communications, steal sensitive information, or gain insights into network operations.

Which vulnerability can arise from outdated firmware?

Answer: Exploitable vulnerabilities

Outdated firmware often contains known security vulnerabilities that have been discovered and, in many cases, publicly disclosed. Manufacturers release firmware updates specifically to patch these security flaws, improve performance, or add new features. Failing to update firmware leaves devices susceptible to exploitation by attackers who can leverage these known vulnerabilities to gain unauthorized access, disrupt operations, or install malicious software.

Why should unused services be disabled on a network device?

Answer: To reduce attack surface

Disabling unused services on a network device is a fundamental security best practice. Every active service represents a potential entry point or 'attack surface' that an attacker could exploit. By turning off services that are not essential for the device's function, administrators significantly reduce the number of potential vulnerabilities and the overall attack surface, thereby enhancing the device's security posture.