# OWASP Top 10
PDM Domain(s): Risk Governance & Assurance (RGA), Vulnerability and Surface Defense (VSD), Security Posture and Hygiene (SPH)
The OWASP Top 10 is a standard awareness document published by the Open Web Application Security Project that represents a broad consensus on the most critical security risks to web applications. Updated every three to four years based on data from hundreds of organizations and vulnerability databases, the current 2021 edition categorizes risks including Broken Access Control, Cryptographic Failures, Injection, Insecure Design, Security Misconfiguration, Vulnerable and Outdated Components, Identification and Authentication Failures, Software and Data Integrity Failures, Security Logging and Monitoring Failures, and Server-Side Request Forgery.
The document exists because application security is complex, but most organizations need a starting point. Security teams cannot test for every possible vulnerability. Developers cannot remember every secure coding practice. Auditors cannot evaluate every attack vector. The OWASP Top 10 solves this prioritization problem by identifying the risks that appear most frequently in real-world attacks and have the highest business impact when exploited.
This makes the Top 10 more than an educational resource. It functions as a de facto industry standard. Major compliance frameworks reference it directly. PCI DSS requires addressing OWASP vulnerabilities in web-facing applications that process cardholder data. ISO 27001 assessments frequently use the Top 10 as evidence that organizations understand application security fundamentals. The document shapes security tool development, training curricula, and assessment methodologies across the cybersecurity industry.
The OWASP Top 10 compilation process combines quantitative data analysis with qualitative community input to identify the most critical application security risks. OWASP collects vulnerability data from application security vendors, bug bounty platforms, consulting firms, and organizations willing to share anonymized findings. This data covers hundreds of thousands of applications across different industries, technologies, and geographic regions.
The ranking methodology evaluates four factors: exploitability, prevalence, detectability, and technical impact. Exploitability measures how easy it is for attackers to exploit the vulnerability. Prevalence indicates how frequently the vulnerability appears in real applications. Detectability assesses how readily security tools and manual testing can identify the weakness. Technical impact quantifies the potential damage if the vulnerability is successfully exploited.
Each Top 10 category includes detailed guidance structured around three components: description, example attack scenarios, and prevention measures. The description explains the vulnerability class in technical terms while remaining accessible to non-security professionals. Attack scenarios provide concrete examples of how adversaries exploit the weakness in practice. Prevention guidance offers specific technical controls and secure development practices to eliminate or mitigate the risk.
Take Broken Access Control, the number one risk in the 2021 edition. The description explains that access control enforces policy such that users cannot act outside of their intended permissions. Common weaknesses include bypassing access control checks by modifying URLs or HTML pages, allowing primary keys to be changed to access other users' records, and elevation of privilege attacks where users act as administrators without being logged in as administrators.
The attack scenarios section provides realistic examples. An attacker modifies the browser URL from /app/accountInfo?account=12345 to /app/accountInfo?account=67890 and accesses another user's account information. A SQL injection vulnerability allows an attacker to access unauthorized data by manipulating database queries. An authenticated user gains administrator privileges by modifying their session cookie or JWT token.
Prevention guidance includes technical controls like denying access by default, implementing access control mechanisms once and reusing them throughout the application, minimizing Cross-Origin Resource Sharing (CORS) usage, and logging access control failures while alerting administrators when appropriate.
Organizations implement the OWASP Top 10 through multiple operational mechanisms. Development teams use it as acceptance criteria in secure development lifecycle processes, requiring applications to pass Top 10 testing before production deployment. Security teams incorporate it into penetration testing methodologies, ensuring assessments cover all ten risk categories. Training programs use the Top 10 as curriculum structure for developer security awareness initiatives.
The document also influences tool selection and configuration. Static Application Security Testing (SAST) tools market their coverage of OWASP Top 10 categories. Dynamic Application Security Testing (DAST) scanners structure their testing modules around Top 10 risks. Security orchestration platforms use the Top 10 as a classification system for vulnerability prioritization and remediation workflows.
Many organizations create OWASP Top 10 compliance dashboards that track remediation progress across application portfolios. These dashboards typically display metrics like percentage of applications tested for each risk category, average time to remediate findings, and trend analysis showing improvement or degradation over time. This operational approach transforms the Top 10 from an awareness document into a measurable security program component.
Web application vulnerabilities represent one of the most exploited attack vectors in modern cybersecurity. The 2023 Verizon Data Breach Investigations Report found that web applications were involved in 26% of breaches, making them the second most common attack pattern after basic web application attacks. The economic impact is substantial: the average cost of a data breach involving web application vulnerabilities exceeded $4.5 million according to IBM's 2023 Cost of a Data Breach Report.
The OWASP Top 10 addresses a fundamental challenge in application security: resource allocation. Security teams cannot test for every possible vulnerability. Development organizations cannot implement every security control. Risk management requires prioritization, and the Top 10 provides an evidence-based framework for focusing effort on the most critical risks.
This prioritization becomes especially important as application portfolios grow larger and more complex. Modern enterprises often manage hundreds or thousands of web applications across different technologies, platforms, and development teams. Without a standardized approach to application security, these organizations face inconsistent security postures, duplicated effort, and gaps in critical areas.
The failure to address OWASP Top 10 vulnerabilities has resulted in numerous high-profile breaches. The 2017 Equifax breach exploited an unpatched Apache Struts vulnerability, which falls under the "Vulnerable and Outdated Components" category. The 2019 Capital One breach involved a misconfigured Web Application Firewall and overly permissive IAM roles, representing "Security Misconfiguration" risks. The 2020 SolarWinds supply chain attack demonstrated "Software and Data Integrity Failures" on a massive scale.
A common misconception is that the OWASP Top 10 represents a complete application security program. Organizations sometimes treat Top 10 compliance as sufficient security rather than a foundational baseline. This approach creates dangerous gaps because the Top 10 focuses on the most common and impactful risks, not all possible risks. Application security requires additional considerations including threat modeling, secure architecture design, security testing integration, and incident response planning.
Another misconception involves the relationship between automated tools and OWASP Top 10 coverage. While security scanning tools often advertise comprehensive Top 10 coverage, automated testing cannot identify all instances of these vulnerability classes. Many OWASP risks require manual testing, business logic analysis, and contextual assessment that exceeds current automation capabilities.
The business impact extends beyond direct breach costs to include regulatory compliance, customer trust, and competitive positioning. Organizations that cannot demonstrate mature application security practices face increasing scrutiny from regulators, customers, and business partners. The OWASP Top 10 provides a recognized framework for communicating security competence to external stakeholders and establishing baseline expectations for vendor assessments and third-party risk management.
CDA approaches the OWASP Top 10 through the lens of Perpetual Compliance Assurance (PCA), where compliance is not an event but a continuous state of readiness. Traditional organizations treat OWASP Top 10 assessment as a periodic activity: annual penetration tests, quarterly scans, or milestone-based security reviews. This episodic approach creates gaps where applications drift from secure baselines between assessment cycles.
The Risk Governance & Assurance (RGA) domain owns OWASP Top 10 implementation at the strategic level, establishing policies, standards, and governance frameworks that ensure consistent application across the organization. RGA defines what constitutes acceptable risk for each OWASP category, establishes remediation timelines, and creates accountability mechanisms for ongoing compliance maintenance.
Vulnerability and Surface Defense (VSD) operationalizes OWASP Top 10 controls through continuous monitoring and assessment. Rather than periodic testing, VSD implements always-on detection capabilities that identify OWASP risks as they emerge. This includes integrating SAST and DAST tools into CI/CD pipelines, deploying runtime application self-protection (RASP) technologies, and maintaining threat intelligence feeds that correlate emerging attack patterns with OWASP categories.
Security Posture and Hygiene (SPH) ensures that OWASP Top 10 controls remain effective over time through configuration management, patch management, and security maintenance processes. SPH prevents the drift that occurs when initially secure applications accumulate misconfigurations, outdated components, and security debt through normal operational changes.
CDA's approach differs from conventional thinking by treating OWASP Top 10 compliance as a measurable state rather than a testing outcome. Most organizations ask: "Did we pass our OWASP Top 10 assessment?" CDA asks: "What is our current OWASP Top 10 compliance posture, and how do we maintain it continuously?"
This perspective requires different metrics and operational processes. Instead of measuring time-to-remediate after vulnerability discovery, CDA measures time-to-detection and prevention-effectiveness rates. Instead of annual compliance reports, CDA maintains real-time compliance dashboards that reflect current state. Instead of remediation projects triggered by audit findings, CDA operates continuous remediation processes that address OWASP risks as part of normal security operations.
The PCA methodology applies to OWASP Top 10 implementation through automated policy enforcement, continuous monitoring, and self-healing security controls. Applications should automatically reject deployments that introduce OWASP risks. Monitoring should continuously validate that OWASP controls remain effective. Infrastructure should automatically remediate common OWASP vulnerabilities without manual intervention.
This approach recognizes that modern application development velocity makes periodic compliance assessment insufficient. Organizations deploying code multiple times per day cannot rely on monthly security testing. CDA's continuous compliance model ensures that OWASP Top 10 protections scale with development velocity while maintaining consistent security posture.
• The OWASP Top 10 represents industry consensus on the most critical web application security risks, updated every 3-4 years based on real-world vulnerability data from hundreds of organizations
• Each risk category includes technical descriptions, concrete attack scenarios, and specific prevention guidance, making it both an awareness document and an operational security framework
• Organizations should treat the OWASP Top 10 as a foundational baseline rather than a complete application security program, requiring additional controls for comprehensive protection
• Effective implementation requires continuous monitoring and assessment rather than periodic testing, with automated detection and remediation capabilities integrated into development and operations processes
• The business impact of OWASP Top 10 vulnerabilities extends beyond breach costs to include regulatory compliance, customer trust, and competitive positioning in an increasingly security-conscious marketplace
• Penetration Testing Methodologies • Static Application Security Testing (SAST) • Secure Development Lifecycle (SDLC) • Web Application Firewalls (WAF) • Vulnerability Management Programs
• OWASP Foundation. "OWASP Top 10 2021." Open Web Application Security Project, 2021. https://owasp.org/Top10/
• National Institute of Standards and Technology. "NIST Cybersecurity Framework 1.1." NIST Special Publication 800-53, 2018.
• Verizon Enterprise. "2023 Data Breach Investigations Report." Verizon Business, 2023.
• Center for Internet Security. "CIS Controls Version 8." Center for Internet Security, 2021.