How do you prioritize security testing for the OWASP top 10 risks?

1 Understand the OWASP top 10

In order to prioritize security testing for the OWASP top 10 risks, it is essential to understand what they are, how they work, and how they can impact your application. Risks include injection, broken authentication, sensitive data exposure, XML external entities (XXE), broken access control, security misconfiguration, and cross-site scripting (XSS). They also account for insecure deserialization, using components with known vulnerabilities, and insufficient logging and monitoring. Injection occurs when malicious data is sent to an application that can execute on the server and compromise the system or data. Broken authentication occurs when an application fails to verify a user's identity or privileges. Sensitive data exposure happens when an application does not protect confidential information from being stolen or leaked. XML external entities (XXE) can disclose confidential information or execute malicious code when an application processes XML input containing references to external entities. Broken access control occurs when proper restrictions on what users can do or see are not enforced. Security misconfiguration happens when an application is not configured securely, leaving it vulnerable to attacks or exposing unnecessary information. Cross-site scripting (XSS) can occur when user input or output is not sanitized properly, allowing attackers to inject malicious scripts that can execute on the browser. Insecure deserialization happens when untrusted data is deserialized that can contain malicious code or tamper with the application logic or state. Using components with known vulnerabilities occurs when third-party libraries, frameworks, or software are used that have known security flaws that can be exploited by attackers. Insufficient logging and monitoring happens when security events such as attacks, errors, or anomalies are not recorded or alerted on which could indicate a breach or help in the investigation and response.

2 Assess the impact and likelihood of each risk

Assess the impact and likelihood of each risk for your application. The impact refers to the potential damage or loss that an attacker can cause by exploiting a vulnerability, such as data theft, fraud, reputation damage, or legal liability. The likelihood refers to the probability that an attacker will find and exploit a vulnerability, considering factors such as the complexity, the exposure, the motivation, and the skills of the attacker. Use a simple matrix or a scoring system to rank the risks based on their impact and likelihood, and assign them a priority level.

3 Plan and execute security tests based on priority

Plan and execute security tests based on the priority level of each risk. Allocate more time and resources to test the risks that have the highest impact and likelihood, and less time and resources to test the risks that have the lower impact and likelihood. Use appropriate testing techniques and tools to test each risk, such as static analysis, dynamic analysis, penetration testing, code review, or vulnerability scanners. Document test results, report any findings, and recommend any remediation actions.

4 Review and update your security testing strategy

Security testing is not a one-time activity, but a continuous process that requires regular review and update. Monitor your application for any changes or updates that may introduce new vulnerabilities or affect existing ones. Keep track of any new or emerging security risks that may not be covered by the OWASP top 10, and update your security testing strategy accordingly. Measure and improve your security testing effectiveness and efficiency, learning from experience and feedback.

5 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?