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

5. 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?"