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
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
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
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
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?"
When to Use
This skill is applicable to execute the workflow or actions described in the overview.
Limitations
- Use this skill only when the task clearly matches the scope described above.
- Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
- Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.