OWASP Top 10 Checker Skill

Purpose

This skill provides systematic verification of application compliance with the OWASP Top 10 2021 security standards, ensuring comprehensive security coverage across all critical categories.

When to Use

• Final security validation before deployment
• Security certification and compliance
• Security audit preparation
• Post-remediation verification
• Quarterly security reviews
• Pre-release security checklist

OWASP Top 10 2021 Compliance Workflow

A01:2021 - Broken Access Control

Risk: Users can act outside of their intended permissions

Compliance Checks:

1. Authorization Enforcement:

# Check for authorization decorators/middleware
grep -r "@requires_auth\|@login_required\|@permission_required" src/
grep -r "auth_required\|check_permission" src/

# Find routes without authorization
grep -r "@app.route\|@router.get\|@router.post" src/ --include="*.py" -A 5

Checklist:

• Authorization enforced on every endpoint
• Default deny access control
• Server-side authorization (not client-side only)
• Authorization checked on every request
• Role-based access control (RBAC) implemented
• Ownership verified for object access

2. Insecure Direct Object References (IDOR):

# Look for direct ID usage from requests
grep -r "request.*\['id'\]\|request.*\.id\|params\['id'\]" src/

Checklist:

• No direct object references without validation
• Ownership verified before access
• Indirect references used (e.g., session-based)
• UUID instead of sequential IDs where applicable

3. CORS Configuration:

# Check CORS settings
grep -r "Access-Control-Allow-Origin" src/ config/
grep -r "CORS.*origin" src/ --include="*.py" --include="*.js"

Checklist:

• No wildcard (*) CORS unless absolutely necessary
• Specific origin whitelist configured
• Credentials mode properly configured
• Preflight requests handled correctly

4. Disable Directory Listing:

# Check web server config
grep -r "autoindex\|directory.*listing" config/

Checklist:

• Directory listing disabled
• .git directory not accessible
• Backup files not accessible

Status: ☐ Pass ☐ Fail

---

A02:2021 - Cryptographic Failures

Risk: Sensitive data exposed due to weak or missing encryption

Compliance Checks:

1. Data in Transit:

# Check TLS enforcement
grep -r "SECURE_SSL_REDIRECT\|HTTPS_ONLY\|ssl.*required" config/ src/
grep -r "tls.*version\|ssl.*version" config/

# Check for HTTP usage
grep -r "http://\|ws://" src/ | grep -v "localhost\|127.0.0.1"

Checklist:

• TLS 1.2+ enforced
• TLS 1.0/1.1 disabled
• HTTPS redirect configured
• HSTS header set (max-age >= 31536000)
• Secure WebSocket (wss://) for real-time
• Certificate validation enabled

2. Data at Rest:

# Check for encryption of sensitive data
grep -r "encrypt\|cipher\|AES" src/
grep -r "password.*plain\|password.*clear" src/

Checklist:

• Passwords hashed (bcrypt/argon2/scrypt)
• PII encrypted at rest
• Database encryption enabled for sensitive columns
• Backups encrypted
• Key management system used

3. Weak Cryptography:

# Find weak algorithms
grep -r "md5\|sha1\|DES\|RC4" src/ --include="*.py" --include="*.js"
grep -r "ECB.*mode" src/

Checklist:

• No MD5/SHA1 for security (only for checksums)
• AES-256-GCM or ChaCha20-Poly1305 for encryption
• Argon2id or bcrypt for passwords
• SHA-256/SHA-3 for hashing
• Proper IV/nonce generation
• No ECB mode

4. Random Number Generation:

# Check RNG usage
grep -r "random\.random\|Math\.random" src/
grep -r "secrets\|os\.urandom\|crypto\.randomBytes" src/

Checklist:

• Cryptographically secure RNG (secrets, os.urandom)
• No Math.random() or random.random() for security
• Sufficient entropy for keys/tokens

Status: ☐ Pass ☐ Fail

---

A03:2021 - Injection

Risk: Untrusted data sent to interpreter as command/query

Compliance Checks:

1. SQL Injection Prevention:

# Find string concatenation in SQL
grep -r "execute.*%\|execute.*\+\|execute.*format\|execute.*f\"" src/ --include="*.py"
grep -r "SELECT.*\+\|INSERT.*\+\|UPDATE.*\+\|DELETE.*\+" src/

Checklist:

• Parameterized queries/prepared statements
• ORM used correctly (no raw SQL with user input)
• No string concatenation in SQL
• Input validation on all parameters
• Least privilege database accounts

2. Command Injection Prevention:

# Find shell command execution
grep -r "subprocess.*shell=True\|os\.system\|os\.popen" src/ --include="*.py"
grep -r "exec\|eval\|child_process" src/ --include="*.js"

Checklist:

• No shell=True with user input
• Command arguments as list, not string
• Input validation/sanitization
• Whitelist allowed commands
• No eval() or exec() with user input

3. LDAP Injection:

grep -r "ldap.*search\|ldap.*filter" src/

Checklist:

• LDAP queries parameterized
• Special characters escaped
• Input validation

4. NoSQL Injection:

grep -r "find.*\$where\|\.exec(" src/ --include="*.js"

Checklist:

• MongoDB operators sanitized
• $where clauses avoided or validated
• Input type validation

5. Template Injection:

grep -r "render_template_string\|Jinja2.*from_string" src/
grep -r "autoescape.*False" src/

Checklist:

• No user input in template compilation
• Auto-escaping enabled
• Safe template rendering

Status: ☐ Pass ☐ Fail

---

A04:2021 - Insecure Design

Risk: Missing or ineffective security controls in design

Compliance Checks:

1. Threat Modeling:

Checklist:

• Threat model documented
• Attack surface analyzed
• Trust boundaries identified
• Data flow diagrams created
• Security requirements defined

2. Security Design Patterns:

Checklist:

• Defense in depth implemented
• Fail securely (errors don't expose data)
• Least privilege principle
• Separation of duties
• Complete mediation (check every access)

3. Rate Limiting:

grep -r "rate.*limit\|throttle" src/ config/

Checklist:

• Rate limiting on authentication endpoints
• Rate limiting on API endpoints
• Account lockout after failed attempts
• CAPTCHA for public forms

4. Business Logic:

Checklist:

• Transaction integrity enforced
• Workflow state validated
• Resource limits defined
• Input bounds checked
• Edge cases handled

Status: ☐ Pass ☐ Fail

---

A05:2021 - Security Misconfiguration

Risk: Insecure default configurations, incomplete setups

Compliance Checks:

1. Security Headers:

# Check for security headers
grep -r "X-Frame-Options\|X-Content-Type-Options\|Content-Security-Policy" src/ config/
grep -r "Strict-Transport-Security\|X-XSS-Protection" src/ config/

Checklist:

• X-Frame-Options: DENY or SAMEORIGIN
• X-Content-Type-Options: nosniff
• Content-Security-Policy configured
• Strict-Transport-Security: max-age=31536000
• X-XSS-Protection: 1; mode=block
• Referrer-Policy: strict-origin-when-cross-origin

2. Error Handling:

# Check debug mode
grep -r "DEBUG.*True\|development.*mode" config/ src/
grep -r "traceback\|stack.*trace" src/

Checklist:

• Debug mode disabled in production
• Generic error messages to users
• Detailed errors logged, not displayed
• No stack traces exposed
• Custom error pages configured

3. Default Credentials:

# Find hardcoded credentials
grep -r "password.*=.*admin\|password.*=.*password" src/ config/

Checklist:

• All default credentials changed
• No hardcoded passwords
• Credentials in environment variables
• Secrets management system used

4. Unnecessary Features:

# Check for sample/test code
find . -name "*sample*" -o -name "*test*" -o -name "*demo*" | grep -v node_modules

Checklist:

• Sample code removed
• Unused endpoints disabled
• Test accounts removed
• Development tools disabled in production
• Unnecessary services stopped

5. Missing Patches:

# Check dependency status
pip list --outdated 2>/dev/null || npm outdated 2>/dev/null

Checklist:

• Dependencies up to date
• Security patches applied
• Regular update schedule
• Vulnerability monitoring enabled

Status: ☐ Pass ☐ Fail

---

A06:2021 - Vulnerable and Outdated Components

Risk: Using components with known vulnerabilities

Compliance Checks:

1. Dependency Inventory:

# List all dependencies
pip list --format=json > dependencies.json 2>/dev/null || npm list --json > dependencies.json 2>/dev/null

Checklist:

• Complete dependency inventory (SBOM)
• Direct and transitive dependencies tracked
• License compliance verified
• Dependency sources trusted

2. Vulnerability Scanning:

# Scan for vulnerabilities
pip-audit --format json 2>/dev/null || npm audit --json 2>/dev/null
safety check --json 2>/dev/null

Checklist:

• Regular vulnerability scans (weekly minimum)
• No critical vulnerabilities
• High vulnerabilities remediated
• Vulnerability remediation SLA defined

3. Version Management:

# Check for version pinning
cat requirements.txt setup.py package.json 2>/dev/null

Checklist:

• Versions pinned in lockfiles
• Compatible version ranges defined
• Regular updates scheduled
• Breaking changes reviewed before update

4. Component Retirement:

Checklist:

• No unmaintained dependencies
• EOL software replaced
• Deprecated features not used
• Migration plan for aging components

Status: ☐ Pass ☐ Fail

---

A07:2021 - Identification and Authentication Failures

Risk: Weak authentication allows impersonation

Compliance Checks:

1. Password Policy:

# Check password requirements
grep -r "password.*length\|password.*complexity" src/
grep -r "MIN_PASSWORD_LENGTH\|PASSWORD_VALIDATORS" config/ src/

Checklist:

• Minimum 8 characters (12+ recommended)
• Complexity requirements enforced
• Common passwords blocked
• Password strength meter implemented
• Password history (no reuse)

2. Multi-Factor Authentication:

grep -r "mfa\|2fa\|totp\|two.*factor" src/

Checklist:

• MFA available for sensitive operations
• MFA enforced for admin accounts
• TOTP/hardware token support
• Backup codes provided

3. Session Management:

# Check session configuration
grep -r "SESSION.*TIMEOUT\|session.*expir" config/ src/
grep -r "SESSION_COOKIE_SECURE\|SESSION_COOKIE_HTTPONLY" config/ src/

Checklist:

• Session timeout configured (15-30 min idle)
• Absolute session timeout (e.g., 8 hours)
• Session invalidated on logout
• Secure session cookies (Secure, HttpOnly, SameSite)
• Session fixation prevented (regenerate on login)
• Concurrent session limits

4. Credential Storage:

# Check password hashing
grep -r "bcrypt\|argon2\|scrypt\|pbkdf2" src/
grep -r "hashlib\.md5.*password\|hashlib\.sha1.*password" src/

Checklist:

• Passwords hashed with bcrypt/argon2/scrypt
• Salt unique per password
• Work factor appropriate (bcrypt: 12+, argon2: per OWASP)
• No reversible encryption for passwords

5. Account Enumeration:

# Check error messages
grep -r "user.*not.*found\|invalid.*username" src/

Checklist:

• Generic authentication errors ("Invalid credentials")
• Same response time for valid/invalid users
• Password reset doesn't confirm email existence
• Registration doesn't confirm email existence

6. Brute Force Protection:

grep -r "login.*attempt\|failed.*attempt\|account.*lock" src/

Checklist:

• Account lockout after N failed attempts (5-10)
• Temporary lockout (not permanent)
• Rate limiting on login endpoint
• CAPTCHA after failed attempts
• Login attempt logging

Status: ☐ Pass ☐ Fail

---

A08:2021 - Software and Data Integrity Failures

Risk: Code and infrastructure not protected from integrity violations

Compliance Checks:

1. Insecure Deserialization:

# Check for unsafe deserialization
grep -r "pickle\.loads\|yaml\.load\(" src/ --include="*.py"
grep -r "eval\|unserialize" src/

Checklist:

• No pickle with untrusted data
• yaml.safe_load() used (not yaml.load())
• JSON preferred over pickle
• Deserialization input validated
• No eval() with untrusted data

2. CI/CD Pipeline Security:

Checklist:

• Pipeline configuration in version control
• Code signing for releases
• Secret scanning in CI/CD
• Dependency verification
• Build reproducibility
• Artifact signing
• Deployment approval process

3. Update Mechanism:

Checklist:

• Updates delivered over HTTPS
• Update signatures verified
• Automatic updates signed
• Rollback mechanism available
• Update integrity checked

4. Supply Chain Security:

Checklist:

• Dependencies from trusted sources
• Dependency hash verification
• Software Bill of Materials (SBOM)
• Third-party code reviewed
• Vendor security assessment

Status: ☐ Pass ☐ Fail

---

A09:2021 - Security Logging and Monitoring Failures

Risk: Breaches not detected, incidents not responded to

Compliance Checks:

1. Security Event Logging:

# Check logging implementation
grep -r "logging\|logger\|log\." src/ --include="*.py" --include="*.js"
grep -r "audit.*log\|security.*log" src/

Checklist:

• Authentication events logged (success/failure)
• Authorization failures logged
• Input validation failures logged
• Sensitive operations logged
• Administrative actions logged
• Access to sensitive data logged

2. Log Content:

Checklist:

• Timestamp (UTC)
• User/session identifier
• Action performed
• Resource accessed
• Source IP address
• Outcome (success/failure)
• No sensitive data in logs (passwords, tokens, PII)

3. Log Protection:

# Check log file permissions
find . -name "*.log" -ls 2>/dev/null

Checklist:

• Log files write-only for application
• Logs protected from tampering
• Logs rotated regularly
• Log retention policy defined
• Logs backed up
• Centralized logging implemented

4. Monitoring and Alerting:

Checklist:

• Real-time security monitoring
• Automated alerting configured
• Failed login threshold alerts
• Unusual activity detection
• Anomaly detection
• Security dashboard available

5. Incident Response:

Checklist:

• Incident response plan documented
• Response team identified
• Alert escalation procedures
• Incident logging and tracking
• Post-incident review process

Status: ☐ Pass ☐ Fail

---

A10:2021 - Server-Side Request Forgery (SSRF)

Risk: Application fetches remote resources without validating user-supplied URL

Compliance Checks:

1. URL Validation:

# Find URL fetching code
grep -r "requests\.get\|urllib\.request\|fetch\|axios\.get" src/
grep -r "url.*request\|user.*url" src/

Checklist:

• User-supplied URLs validated
• URL whitelist implemented
• Protocol whitelist (HTTP/HTTPS only)
• Private IP ranges blocked
• DNS rebinding protection
• URL redirection limited

2. Network Segmentation:

Checklist:

• Application in DMZ
• Internal services not accessible from app
• Firewall rules deny by default
• Outbound traffic restricted
• Service mesh/network policies configured

3. Input Validation:

# Check for URL sanitization
grep -r "validate.*url\|sanitize.*url\|parse.*url" src/

Checklist:

• URL parsing and validation
• Hostname validation
• Port restrictions
• Path normalization
• No file:// protocol
• No access to metadata services (169.254.169.254)

Status: ☐ Pass ☐ Fail

---

Overall Compliance Report Format

# OWASP Top 10 2021 Compliance Report

**Date**: [YYYY-MM-DD]
**Application**: [name]
**Assessed By**: OWASP Checker

## Compliance Summary

| Category | Status | Critical Issues | Notes |
|----------|--------|-----------------|-------|
| A01 - Broken Access Control | ✅/⚠️/❌ | [count] | [summary] |
| A02 - Cryptographic Failures | ✅/⚠️/❌ | [count] | [summary] |
| A03 - Injection | ✅/⚠️/❌ | [count] | [summary] |
| A04 - Insecure Design | ✅/⚠️/❌ | [count] | [summary] |
| A05 - Security Misconfiguration | ✅/⚠️/❌ | [count] | [summary] |
| A06 - Vulnerable Components | ✅/⚠️/❌ | [count] | [summary] |
| A07 - Auth Failures | ✅/⚠️/❌ | [count] | [summary] |
| A08 - Integrity Failures | ✅/⚠️/❌ | [count] | [summary] |
| A09 - Logging Failures | ✅/⚠️/❌ | [count] | [summary] |
| A10 - SSRF | ✅/⚠️/❌ | [count] | [summary] |

**Legend**:
- ✅ Pass: Fully compliant
- ⚠️ Partial: Some issues, not critical
- ❌ Fail: Critical issues found

**Overall Compliance**: [XX]% ([X]/10 categories passed)

## Critical Findings

[List all critical non-compliance items that must be fixed]

## Recommendations

### Immediate (Critical)
1. [Item]

### Short-term (High)
1. [Item]

### Long-term (Medium)
1. [Item]

## Certification

This application [IS / IS NOT] compliant with OWASP Top 10 2021 standards.

**Assessor**: [name]
**Date**: [YYYY-MM-DD]
**Next Assessment**: [YYYY-MM-DD]

---

Best Practices

Assessment Process:

• Complete all categories
• Document evidence for each check
• Retest after remediation
• Keep assessment current (quarterly)

Compliance Tracking:

• Track compliance over time
• Maintain compliance dashboard
• Regular reassessment (quarterly)
• Update after major changes

Remediation:

• Fix critical items immediately
• Schedule high/medium items
• Document compensating controls
• Verify fixes effectiveness

Documentation:

• Keep detailed compliance records
• Document exceptions with justification
• Track remediation progress
• Maintain audit trail

---

Integration with Security Workflow

Input: Implemented and tested application Process: Systematic OWASP Top 10 compliance verification Output: Compliance report with certification status Next Step: Security certification or deployment approval

---

Remember

• Compliance is not security: OWASP Top 10 is baseline, not complete security
• Context matters: Adapt checks to your application type
• Defense in depth: Multiple layers of controls
• Continuous compliance: Not a one-time check
• Document everything: Maintain audit trail
• Stay current: OWASP Top 10 updates periodically

Your goal is to ensure applications meet OWASP Top 10 security standards and maintain compliance over time.