OWASP Top 10 Frequency Analysis — How Often Each Vulnerability Appears
Data-driven breakdown of OWASP Top 10 2021 vulnerability categories ranked by real-world frequency. Sourced from Stack Overflow developer questions, CVE databases, and OWASP incidence data.
By Michael Lip · Updated April 2026
Methodology
Data was collected on April 10, 2026 using the Stack Overflow public API (/2.3/search endpoint) with queries for OWASP-related and security vulnerability topics. We cross-referenced 60 Stack Overflow questions (30 OWASP-specific, 30 vulnerability-tagged) with OWASP's published incidence rates from the 2021 Top 10 report and CVE database statistics. SO question counts represent aggregate tagged questions; CVE counts represent 2024 filings per category. Incidence rates are from OWASP's original application testing data.
| OWASP ID | Category | Incidence Rate | CVEs (2024) | SO Questions | Avg CVSS | Severity | Top Mitigation |
|---|---|---|---|---|---|---|---|
| A01:2021 | Broken Access Control | 94.0% | 34,322 | ~34,200 | 7.6 | Critical | Deny by default; enforce ownership checks server-side |
| A02:2021 | Cryptographic Failures | 80.2% | 18,450 | ~28,500 | 7.2 | High | Use TLS 1.3; never store plaintext secrets; use strong KDFs |
| A03:2021 | Injection (SQL, XSS, LDAP) | 72.1% | 28,765 | ~91,800 | 8.1 | Critical | Parameterized queries; input validation; CSP headers |
| A04:2021 | Insecure Design | 67.5% | 12,100 | ~15,700 | 6.8 | High | Threat modeling; secure design patterns; abuse case testing |
| A05:2021 | Security Misconfiguration | 69.8% | 22,340 | ~45,600 | 6.5 | High | Automated hardening; minimal installs; disable defaults |
| A06:2021 | Vulnerable & Outdated Components | 63.4% | 31,200 | ~27,900 | 7.4 | High | Dependency scanning; SBOM; automated updates |
| A07:2021 | Identification & Authentication Failures | 55.8% | 14,800 | ~25,900 | 7.8 | Critical | MFA; rate limiting; credential stuffing protection |
| A08:2021 | Software & Data Integrity Failures | 47.2% | 9,650 | ~12,200 | 7.0 | High | Verify signatures; use trusted CI/CD; SRI for CDN assets |
| A09:2021 | Security Logging & Monitoring Failures | 44.6% | 5,200 | ~8,400 | 5.5 | Medium | Centralized logging; alerting on auth failures; audit trails |
| A10:2021 | Server-Side Request Forgery (SSRF) | 38.5% | 7,890 | ~6,800 | 8.6 | Critical | Allowlist URLs; disable redirects; sanitize user-supplied URLs |
Real Stack Overflow Questions by Vulnerability Category
Top-voted questions from the Stack Overflow API illustrating each vulnerability type in real developer scenarios.
| Question | OWASP Category | Votes | Views |
|---|---|---|---|
| How serious is this new ASP.NET security vulnerability and how can I workaround it? | A03 — Injection | 192 | 24,919 |
| How can a Format-String vulnerability be exploited? | A03 — Injection | 69 | 91,776 |
| Log4j vulnerability - Is Log4j 1.2.17 vulnerable? | A06 — Outdated Components | 63 | 68,099 |
| Is the Shellshock vulnerability in Bash documented or intentional? | A03 — Injection | 55 | 6,013 |
| Why is using a Non-Random IV with CBC Mode a vulnerability? | A02 — Cryptographic Failures | 49 | 41,331 |
| Application vulnerability due to Non Random Hash Functions | A02 — Cryptographic Failures | 40 | 15,660 |
| Does Log4j security violation vulnerability affect log4net? | A06 — Outdated Components | 34 | 21,387 |
| playframework owasp top 10 | A05 — Misconfiguration | 29 | 3,421 |
| How to fix Path Manipulation Vulnerability in Java? | A01 — Broken Access Control | 22 | 148,460 |
| Disabling Spring Security headers does not work | A05 — Misconfiguration | 19 | 15,586 |
| How to avoid open-redirect vulnerability safely | A01 — Broken Access Control | 19 | 25,942 |
| How to allow specific characters with OWASP HTML Sanitizer? | A03 — Injection | 16 | 19,920 |
| Vulnerability in closed plugin Yuzo Related Posts | A06 — Outdated Components | 16 | 4,199 |
| OWASP top ten attacks and Spring Security | A05 — Misconfiguration | 14 | 15,853 |
| Heap Inspection Security Vulnerability | A02 — Cryptographic Failures | 15 | 45,025 |
Frequently Asked Questions
What is the most common OWASP Top 10 vulnerability?
Broken Access Control (A01:2021) is the most common OWASP Top 10 vulnerability, appearing in 94% of tested applications according to OWASP data. It moved up from fifth position in the 2017 list, reflecting its widespread prevalence across web applications. Stack Overflow shows over 34,000 questions tagged with access control and security topics.
How has the OWASP Top 10 changed from 2017 to 2021?
Major changes include Broken Access Control moving from #5 to #1, Cryptographic Failures replacing Sensitive Data Exposure at #2, and three new categories added: Insecure Design (A04), Software and Data Integrity Failures (A08), and Server-Side Request Forgery (A10). Injection dropped from #1 to #3, reflecting improved framework-level protections.
What is the difference between OWASP Top 10 for Web and for LLMs?
The OWASP Top 10 for Web Applications covers traditional vulnerabilities like injection, broken authentication, and XSS. The OWASP Top 10 for LLMs addresses AI-specific risks including prompt injection, insecure output handling, training data poisoning, and model denial of service. Both lists share some overlap in areas like insecure design and supply chain security.
How do I protect against injection vulnerabilities?
Protect against injection by using parameterized queries or prepared statements for SQL, employing ORM frameworks that handle escaping, validating and sanitizing all user inputs, implementing Content Security Policy headers to prevent XSS, and using the OWASP ESAPI or similar encoding libraries. For LLM applications, use structured prompt templates and input validation.
Where does this OWASP frequency data come from?
This analysis combines data from the Stack Overflow API (question counts and vote scores for security-related tags), OWASP's own incidence rate data from the 2021 report, and CVE database statistics. Stack Overflow data was fetched via the public API on April 10, 2026. The dataset provides a developer-centric view of which vulnerabilities practitioners encounter most frequently.