Security Threats and Vulnerabilities

Explain why basic security measures are necessary on network devices.

Types of Threats

• Attacks on a network can be devastating and can result in a loss of time and money due to damage, or theft of important information or assets. Intruders can gain access to a network through software vulnerabilities, hardware attacks, or through guessing someone’s username and password. Intruders who gain access by modifying software or exploiting software vulnerabilities are called threat actors.
• After the threat actor gains access to the network, four types of threats may arise:
• • Information Theft
  • Data Loss and manipulation
  • Identity Theft
  • Disruption of Service

Types of Vulnerabilities

• Vulnerability is the degree of weakness in a network or a device.
• Some degree of vulnerability is inherent in routers, switches, desktops, servers, and even security devices.
• Typically, the network devices under attack are the endpoints, such as servers and desktop computers.
• There are three primary vulnerabilities or weaknesses:
• • Technological Vulnerabilities might include TCP/IP Protocol weaknesses, Operating System Weaknesses, and Network Equipment weaknesses.
  • Configuration Vulnerabilities might include unsecured user accounts, system accounts with easily guessed passwords, misconfigured internet services, unsecure default settings, and misconfigured network equipment.
  • Security Policy Vulnerabilities might include lack of a written security policy, politics, lack of authentication continuity, logical access controls not applied, software and hardware installation and changes not following policy, and a nonexistent disaster recovery plan.
• All three of these sources of vulnerabilities can leave a network or device open to various attacks, including malicious code attacks and network attacks.

Physical Security

• If network resources can be physically compromised, a threat actor can deny the use of network resources.
• The four classes of physical threats are as follows:
• • Hardware threats – This includes physical damage to servers, routers, switches, cabling plant, and workstations.
  • Environmental threats – This includes temperature extremes (too hot or too cold) or humidity extremes (too wet or too dry).
  • Electrical threats – This includes voltage spikes, insufficient supply voltage (brownouts), unconditioned power (noise), and total power loss.
  • Maintenance threats – This includes poor handling of key electrical components (electrostatic discharge), lack of critical spare parts, poor cabling, and poor labeling.
• A good plan for physical security must be created and implemented to address these issues.

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