Vulnerability Scanner
Think like an attacker, defend like an expert. 2025 threat landscape awareness.
🔧 Runtime Scripts
Execute for automated validation:
| Script | Purpose | Usage |
|--------|---------|-------|
| scripts/security_scan.py | Validate security principles applied | python scripts/security_scan.py <project_path> |
📋 Reference Files
| File | Purpose | |------|---------| | checklists.md | OWASP Top 10, Auth, API, Data protection checklists |
1. Security Expert Mindset
Core Principles
| Principle | Application | |-----------|-------------| | Assume Breach | Design as if attacker already inside | | Zero Trust | Never trust, always verify | | Defense in Depth | Multiple layers, no single point | | Least Privilege | Minimum required access only | | Fail Secure | On error, deny access |
Threat Modeling Questions
Before scanning, ask:
- What are we protecting? (Assets)
- Who would attack? (Threat actors)
- How would they attack? (Attack vectors)
- What's the impact? (Business risk)
2. OWASP Top 10:2025
Risk Categories
| Rank | Category | Think About | |------|----------|-------------| | A01 | Broken Access Control | Who can access what? IDOR, SSRF | | A02 | Security Misconfiguration | Defaults, headers, exposed services | | A03 | Software Supply Chain 🆕 | Dependencies, CI/CD, build integrity | | A04 | Cryptographic Failures | Weak crypto, exposed secrets | | A05 | Injection | User input → system commands | | A06 | Insecure Design | Flawed architecture | | A07 | Authentication Failures | Session, credential management | | A08 | Integrity Failures | Unsigned updates, tampered data | | A09 | Logging & Alerting | Blind spots, no monitoring | | A10 | Exceptional Conditions 🆕 | Error handling, fail-open states |
2025 Key Changes
2021 → 2025 Shifts:
├── SSRF merged into A01 (Access Control)
├── A02 elevated (Cloud/Container configs)
├── A03 NEW: Supply Chain (major focus)
├── A10 NEW: Exceptional Conditions
└── Focus shift: Root causes > Symptoms
3. Supply Chain Security (A03)
Attack Surface
| Vector | Risk | Question to Ask | |--------|------|-----------------| | Dependencies | Malicious packages | Do we audit new deps? | | Lock files | Integrity attacks | Are they committed? | | Build pipeline | CI/CD compromise | Who can modify? | | Registry | Typosquatting | Verified sources? |
Defense Principles
- Verify package integrity (checksums)
- Pin versions, audit updates
- Use private registries for critical deps
- Sign and verify artifacts
4. Attack Surface Mapping
What to Map
| Category | Elements | |----------|----------| | Entry Points | APIs, forms, file uploads | | Data Flows | Input → Process → Output | | Trust Boundaries | Where auth/authz checked | | Assets | Secrets, PII, business data |
Prioritization Matrix
Risk = Likelihood × Impact
High Impact + High Likelihood → CRITICAL
High Impact + Low Likelihood → HIGH
Low Impact + High Likelihood → MEDIUM
Low Impact + Low Likelihood → LOW
5. Risk Prioritization
CVSS + Context
| Factor | Weight | Question | |--------|--------|----------| | CVSS Score | Base severity | How severe is the vuln? | | EPSS Score | Exploit likelihood | Is it being exploited? | | Asset Value | Business context | What's at risk? | | Exposure | Attack surface | Internet-facing? |
Prioritization Decision Tree
Is it actively exploited (EPSS >0.5)?
├── YES → CRITICAL: Immediate action
└── NO → Check CVSS
├── CVSS ≥9.0 → HIGH
├── CVSS 7.0-8.9 → Consider asset value
└── CVSS <7.0 → Schedule for later
6. Exceptional Conditions (A10 - New)
Fail-Open vs Fail-Closed
| Scenario | Fail-Open (BAD) | Fail-Closed (GOOD) | |----------|-----------------|---------------------| | Auth error | Allow access | Deny access | | Parsing fails | Accept input | Reject input | | Timeout | Retry forever | Limit + abort |
What to Check
- Exception handlers that catch-all and ignore
- Missing error handling on security operations
- Race conditions in auth/authz
- Resource exhaustion scenarios
7. Scanning Methodology
Phase-Based Approach
1. RECONNAISSANCE
└── Understand the target
├── Technology stack
├── Entry points
└── Data flows
2. DISCOVERY
└── Identify potential issues
├── Configuration review
├── Dependency analysis
└── Code pattern search
3. ANALYSIS
└── Validate and prioritize
├── False positive elimination
├── Risk scoring
└── Attack chain mapping
4. REPORTING
└── Actionable findings
├── Clear reproduction steps
├── Business impact
└── Remediation guidance
8. Code Pattern Analysis
High-Risk Patterns
| Pattern | Risk | Look For |
|---------|------|----------|
| String concat in queries | Injection | "SELECT * FROM " + user_input |
| Dynamic code execution | RCE | eval(), exec(), Function() |
| Unsafe deserialization | RCE | pickle.loads(), unserialize() |
| Path manipulation | Traversal | User input in file paths |
| Disabled security | Various | verify=False, --insecure |
Secret Patterns
| Type | Indicators |
|------|-----------|
| API Keys | api_key, apikey, high entropy |
| Tokens | token, bearer, jwt |
| Credentials | password, secret, key |
| Cloud | AWS_, AZURE_, GCP_ prefixes |
9. Cloud Security Considerations
Shared Responsibility
| Layer | You Own | Provider Owns | |-------|---------|---------------| | Data | ✅ | ❌ | | Application | ✅ | ❌ | | OS/Runtime | Depends | Depends | | Infrastructure | ❌ | ✅ |
Cloud-Specific Checks
- IAM: Least privilege applied?
- Storage: Public buckets?
- Network: Security groups tightened?
- Secrets: Using secrets manager?
10. Anti-Patterns
| ❌ Don't | ✅ Do | |----------|-------| | Scan without understanding | Map attack surface first | | Alert on every CVE | Prioritize by exploitability + asset | | Ignore false positives | Maintain verified baseline | | Fix symptoms only | Address root causes | | Scan once before deploy | Continuous scanning | | Trust third-party deps blindly | Verify integrity, audit code |
11. Reporting Principles
Finding Structure
Each finding should answer:
- What? - Clear vulnerability description
- Where? - Exact location (file, line, endpoint)
- Why? - Root cause explanation
- Impact? - Business consequence
- How to fix? - Specific remediation
Severity Classification
| Severity | Criteria | |----------|----------| | Critical | RCE, auth bypass, mass data exposure | | High | Data exposure, privilege escalation | | Medium | Limited scope, requires conditions | | Low | Informational, best practice |
Remember: Vulnerability scanning finds issues. Expert thinking prioritizes what matters. Always ask: "What would an attacker do with this?"