What Are Network Security Threats?

Network security threats are the potential to use and exploit vulnerabilities in connected computational resources. Cyberthreats to a secure ecosystem are ever-evolving, and the sophistication of attacks is increasing. They lurk over data security and inflict devastating financial and operational outcomes on businesses of all sizes.

The world of cybersecurity must anticipate the next malicious agent and proactively design a response to prevent damage or disruption to networks. No longer the malicious actions of an isolated hacker, recent cyberattacks have been conducted by large criminal groups and state-sponsored organizations engaged in espionage. To be successful, a proactive approach to cybersecurity needs to address all types of threats to network security.

What Are Common Network Security Threats?

Network security threats and vulnerabilities take on many forms and can originate from a number of sources. The perpetrators can range from cybercriminals, nation-state actors half a globe away or an individual within the organization just down the hall. The types of threats to network security fall into nine main categories:

• Malware/ransomware
• Denial of Service (DoS) attacks
• Social engineering
• Man-in-the-middle attacks
• Computer viruses
• Zero-day exploits
• Password attacks
• Internet of Things (IoT) attacks
• Injection attacks

Malware/ransomware

The most common threat, malware is defined as malicious software designed to harm a computer system or a network. Malware is a broad category encompassing:

• Ransomware: Locks down data and releases it in exchange for financial gain.
• Spyware: Steals sensitive data, including passwords or credit card numbers.
• Trojan horse threats: Creates back doors to system access or downloads other malware through software hidden inside a seemingly innocuous download.
• Worms: Spreads across a network without human interaction through self-replicating programs.

Denial of Service (DoS) attacks

Designed to overwhelm and shut down a website, application or system, Denial of Service (DoS) attacks send a large volume of data traffic to a target. They take on two basic variations:

• Denial of Service (DoS) attacks
• Distributed Denial of Service (DDoS) attacks

The objective of both forms is to cause the targeted server to deny service to legitimate users. A DoS attack is usually launched from one computer to render servers inoperable with a flood of requests. One of the most common types of threats in network security, a DDoS attack relies on botnets, which are infestations of malware across internet-connected devices. Proactive security measures are essential for the prevention of DDoS attacks.

Social engineering

Confidential financial information is often given unknowingly to cybercriminals. Phishing is the most common of the social engineering cyberattacks, which affects individuals and corporations. It is designed to engage human targets with fraudulent emails, SMS messages or voice calls to execute malicious code or reveal personal information — usually financially sensitive data — for the purpose of theft. Sometimes used in concert with phishing, DNS spoofing is a technique that uses fake web domains to deceive users to give up personal information.

Man-in-the-middle attacks

Unsecured networks and weakly encrypted data are especially susceptible to the man-in-the-middle cyberthreat. Data flows are intercepted, decrypted and read by eavesdroppers who steal or alter sensitive information. Hackers then use login credentials and financial instruments to hijack accounts. Man-in-the-middle attacks are a major contributor to identity theft and can lead to several common network security threats.

Computer viruses

Computer viruses are a common form of self-propagating malware but can be triggered by some human interaction. They are intended to disrupt systems by causing damage to data and/or software. Viruses spread from one computer to another and are often embedded in an otherwise legitimate piece of code or document. Evidence of an infection include:

• Impaired computer performance
• Unexplained password changes
• Unexplained settings changes
• Frequent browser pop-ups
• System crashes

Zero-day exploits

Software and firmware sometimes contain security flaws that lie undetected. If a cybercriminal discovers this vulnerability and acts on it before the publisher can patch it, it is a zero-day exploit—named for leaving no time to react before the attack occurs. They are among the most common and severe network security threats. Zero-day vulnerabilities pose an extreme security threat, especially when targeting operating systems. Patch and vulnerability management are essential to prevent zero-day exploits.

Password attacks

Password attacks can leverage passwords stolen from social engineering attacks. Additionally, they can take the form of brute force attacks by bombarding a server with generated password combinations until access is obtained. Compromised user account credentials are common among network security threats, yet one of the more easily preventable forms of cybercrime. Methods to prevent password attacks include:

• Stronger passwords
• Mandatory and frequent password changes
• Two-factor authentication
• Zero Trust Network Access (ZTNA)

Implementing Zero Trust Network Access (ZTNA) strategies all but eliminates the risk of password attack by applying granular and dynamic policies for users to access network resources.

Internet of Things attacks

Any smart device that can link and transmit data can be a target of an attack on internet-connected devices. Botnets scan for vulnerabilities in firmware and make changes to take over the device, steal data or otherwise access it for malicious intent. An IoT attack resulting in a network breach can be devastating to businesses by causing a DDoS attack, spying on communications or stealing sensitive data. Essential steps for IoT cybersecurity include:

• Locking down IoT-connected devices by changing passwords
• Carefully maintaining an inventory of permitted devices
• Blocking unauthorized devices
• Regularly conducting firmware updates

Injection attacks

Any cyberattack in which a hacker injects code into an existing program, script or query is a type of injection attack. The purpose is to execute remote commands to enable access or to alter data in an otherwise protected webpage or database. These attacks exploit vulnerabilities in a target application, allowing the attacker to execute unauthorized commands. Injection attacks present a critical threat to digital assets. They are detectable by security applications that scan code for signatures and can be prevented with input validation and regular software updates.

Modern cybersecurity solutions are critical in preventing potentially devastating damage to finances and disruption of business operations. Lumen^® Security Solutions provide the tools, actionable intelligence, latest attack trends and mitigation strategies to keep your data secure. With robust detection and customization capabilities, our solutions add a new layer of defense to your network.

 Explore our solutions and see why Lumen is a valuable partner for your cybersecurity strategy.

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