Threat assessment modeling is a critical process in identifying, categorizing, and evaluating potential security threats to applications, systems, and networks. One popular threat modeling framework is STRIDE, which categorizes threats into six distinct types, helping security professionals systematically assess and address potential vulnerabilities. Here’s a detailed explanation of the STRIDE framework and its components:

STRIDE Framework

STRIDE is an acronym that stands for Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, and Elevation of Privilege. Each category represents a type of threat that can affect the security of an application or system. Understanding each component of STRIDE helps in developing a comprehensive threat assessment.

1. Spoofing:
   • Definition: Spoofing involves an attacker impersonating another entity to gain unauthorized access to a system or data.
   • Examples:
     • IP Address Spoofing: Falsifying the source IP address in a packet to make it appear as though it comes from a trusted source.
     • MAC Address Spoofing: Changing the MAC address to impersonate another device on the network.
     • Username Spoofing: Using a falsified username to gain access to a system.
   • Impact: Spoofing can lead to unauthorized access, data breaches, and further exploitation of the system.
2. Tampering:
   • Definition: Tampering refers to unauthorized modification of data, whether it’s in transit or at rest.
   • Examples:
     • Data Tampering: Altering data in a database to falsify records.
     • Message Tampering: Intercepting and modifying a message before it reaches its intended recipient.
   • Impact: Tampering affects the integrity and availability of data, leading to potential data corruption, fraud, or disruption of services.
3. Repudiation:
   • Definition: Repudiation occurs when a user or attacker denies having performed an action, making it difficult to prove responsibility for the activity.
   • Examples:
     • Transaction Denial: A user denies having made a particular transaction, leading to disputes.
     • Activity Denial: An attacker denies having sent a message or altered a file.
   • Impact: Repudiation can undermine the accountability of actions, making it difficult to track and respond to malicious activities.
4. Information Disclosure:
   • Definition: Information disclosure involves the unauthorized exposure of sensitive or confidential information.
   • Examples:
     • Data Leakage: Sensitive data, such as personal information, being exposed to unauthorized parties.
     • Unintended Information Exposure: Sensitive information being inadvertently included in logs or error messages.
   • Impact: Information disclosure can lead to privacy violations, data breaches, and compliance issues.
5. Denial of Service (DoS):
   • Definition: A Denial of Service attack aims to disrupt the availability of a system or service, making it inaccessible to legitimate users.
   • Examples:
     • Network Flooding: Overwhelming a server with excessive traffic, causing it to crash or become unresponsive.
     • Resource Exhaustion: Consuming all available resources on a system, preventing it from functioning properly.
   • Impact: DoS attacks can cause significant disruption to services, leading to loss of revenue, customer dissatisfaction, and potential damage to reputation.
6. Elevation of Privilege:
   • Definition: Elevation of privilege occurs when an attacker gains higher access rights or privileges than they are entitled to, often exploiting vulnerabilities in the system.
   • Examples:
     • Privilege Escalation: Exploiting a vulnerability to gain administrative rights on a system.
     • Access Control Bypass: Circumventing access controls to gain unauthorized privileges.
   • Impact: Elevation of privilege can lead to complete system compromise, allowing the attacker to perform unauthorized actions such as installing malware or exfiltrating data.

Application of STRIDE

• Threat Identification: STRIDE helps security teams identify potential threats during the design and development phases of a system or application.
• Risk Assessment: Each identified threat can be assessed for its likelihood and impact, helping prioritize mitigation efforts.
• Security Controls: STRIDE informs the implementation of specific security controls to mitigate each category of threats, such as using authentication mechanisms to prevent spoofing, encryption to protect against tampering, and logging to counter repudiation.

Summary

The STRIDE framework provides a structured approach to threat assessment, categorizing threats into six types: Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, and Elevation of Privilege. By applying STRIDE, organizations can better understand the security risks they face and implement appropriate controls to protect their systems and data.