gabrielmoreira Vulnerability Assessor Skill
Purpose
This skill provides deep analysis of security vulnerabilities, evaluating exploitability, assessing business impact, calculating risk scores, and providing detailed remediation strategies.
When to Use
- After security scanning identifies vulnerabilities
- Need to prioritize security findings
- Assessing exploitability of vulnerabilities
- Calculating CVSS scores
- Creating remediation roadmaps
- Risk assessment for security issues
Assessment Workflow
1. Vulnerability Classification
Categorize by Type:
Injection Vulnerabilities:
- SQL Injection (SQLi)
- Command Injection
- Code Injection
- LDAP Injection
- XPath Injection
- NoSQL Injection
- OS Command Injection
Broken Authentication:
- Weak password policies
- Session fixation
- Credential stuffing vulnerabilities
- Insecure authentication tokens
- Missing MFA
Sensitive Data Exposure:
- Unencrypted data in transit
- Unencrypted data at rest
- Exposed credentials
- PII leakage
- API keys in code
XML External Entities (XXE):
- XML parsing vulnerabilities
- External entity injection
- DTD injection
Broken Access Control:
- Insecure direct object references (IDOR)
- Missing authorization checks
- Privilege escalation
- CORS misconfiguration
Security Misconfiguration:
- Default credentials
- Unnecessary features enabled
- Error messages leaking information
- Missing security headers
Cross-Site Scripting (XSS):
- Reflected XSS
- Stored XSS
- DOM-based XSS
Insecure Deserialization:
- Pickle in Python
- Unsafe YAML loading
- JSON deserialization issues
Using Components with Known Vulnerabilities:
- Outdated dependencies
- Unpatched libraries
- Known CVEs
Insufficient Logging & Monitoring:
- Missing security event logging
- No alerting on suspicious activity
- Inadequate audit trails
Deliverable: Categorized vulnerability list
2. Exploitability Assessment
Evaluate Ease of Exploitation:
Easy (High Exploitability):
- Publicly available exploits
- No authentication required
- Automated tools can exploit
- Simple proof of concept
- Wide attack surface
Medium Exploitability:
- Requires some technical knowledge
- Authentication needed but weak
- Manual exploitation required
- Specific conditions must be met
- Limited attack surface
Hard (Low Exploitability):
- Deep technical expertise required
- Strong authentication needed
- Complex exploitation chain
- Rare conditions required
- Very limited attack surface
Assessment Criteria:
- Attack vector (Network, Adjacent, Local, Physical)
- Attack complexity (Low, High)
- Privileges required (None, Low, High)
- User interaction (None, Required)
- Available exploit code
- Known exploitation in the wild
Deliverable: Exploitability rating for each vulnerability
3. Impact Analysis
Assess Business Impact:
Confidentiality Impact:
- None: No information disclosure
- Low: Minimal sensitive data exposed
- High: Significant sensitive data exposed (PII, credentials, business secrets)
Integrity Impact:
- None: No data modification
- Low: Limited data modification
- High: Significant data can be modified/deleted
Availability Impact:
- None: No service disruption
- Low: Minimal performance degradation
- High: Service can be completely disrupted (DoS)
Business Impact Examples:
Critical Business Impact:
- Customer data breach
- Financial fraud
- Regulatory compliance violation
- Brand reputation damage
- Complete service outage
High Business Impact:
- Internal data exposure
- Service degradation
- Limited compliance issues
- Moderate reputation risk
Medium Business Impact:
- Information disclosure (non-sensitive)
- Temporary service issues
- Minor compliance concerns
Low Business Impact:
- Minimal data exposure
- No service impact
- Best practice violations
Deliverable: Impact assessment for each vulnerability
4. CVSS Scoring
Calculate CVSS v3.1 Score:
Base Metrics:
Attack Vector (AV):
- Network (N): 0.85
- Adjacent (A): 0.62
- Local (L): 0.55
- Physical (P): 0.2
Attack Complexity (AC):
- Low (L): 0.77
- High (H): 0.44
Privileges Required (PR):
- None (N): 0.85
- Low (L): 0.62 (0.68 if scope changed)
- High (H): 0.27 (0.50 if scope changed)
User Interaction (UI):
- None (N): 0.85
- Required (R): 0.62
Scope (S):
- Unchanged (U)
- Changed (C)
Confidentiality Impact (C):
- None (N): 0.0
- Low (L): 0.22
- High (H): 0.56
Integrity Impact (I):
- None (N): 0.0
- Low (L): 0.22
- High (H): 0.56
Availability Impact (A):
- None (N): 0.0
- Low (L): 0.22
- High (H): 0.56
CVSS Score Ranges:
- 0.0: None
- 0.1-3.9: Low
- 4.0-6.9: Medium
- 7.0-8.9: High
- 9.0-10.0: Critical
Example CVSS Vector:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Score: 9.8 (Critical)
Use CVSS Calculator:
# If available, use online calculator:
# https://www.first.org/cvss/calculator/3.1
Deliverable: CVSS score and vector for each vulnerability
5. Risk Prioritization
Risk Matrix:
| Severity | Exploitability | Priority | SLA |
|---|---|---|---|
| Critical | Easy | P0 | 24 hours |
| Critical | Medium | P0 | 24 hours |
| Critical | Hard | P1 | 7 days |
| High | Easy | P0 | 24 hours |
| High | Medium | P1 | 7 days |
| High | Hard | P2 | 30 days |
| Medium | Easy | P2 | 30 days |
| Medium | Medium | P2 | 30 days |
| Medium | Hard | P3 | 90 days |
| Low | Any | P3 | 90 days |
Priority Definitions:
- P0: Emergency - Fix immediately
- P1: Urgent - Fix this week
- P2: Important - Fix this month
- P3: Normal - Schedule for next release
Additional Risk Factors:
- Publicly disclosed vulnerability
- Active exploitation in the wild
- Compliance requirements (PCI-DSS, HIPAA, GDPR)
- Customer-facing systems
- Access to sensitive data
Deliverable: Prioritized vulnerability list with SLAs
6. Proof of Concept (Safe)
Demonstrate Impact (Safely):
SQL Injection Example:
Input: ' OR '1'='1
Expected: Authentication bypass or data exposure
Actual: [observed behavior]
XSS Example:
Input: <script>alert('XSS')</script>
Expected: Script execution
Actual: [observed behavior]
Path Traversal Example:
Input: ../../etc/passwd
Expected: Access to restricted files
Actual: [observed behavior]
IMPORTANT:
- Only demonstrate in test/dev environments
- Never exploit production systems
- Use safe payloads (alert, not actual malicious code)
- Document all testing activity
- Get authorization before testing
Deliverable: Safe proof of concept for high-priority vulnerabilities
7. Remediation Strategies
Provide Fix Recommendations:
SQL Injection:
# VULNERABLE
cursor.execute(f"SELECT * FROM users WHERE id = {user_id}")
# SECURE
cursor.execute("SELECT * FROM users WHERE id = %s", (user_id,))
Command Injection:
# VULNERABLE
os.system(f"ping {user_input}")
# SECURE
import subprocess
subprocess.run(["ping", "-c", "1", user_input], check=True)
XSS:
// VULNERABLE
element.innerHTML = userInput;
// SECURE
element.textContent = userInput;
// Or use DOMPurify for HTML
element.innerHTML = DOMPurify.sanitize(userInput);
Weak Cryptography:
# VULNERABLE
import hashlib
hash = hashlib.md5(password.encode()).hexdigest()
# SECURE
from passlib.hash import argon2
hash = argon2.hash(password)
Insecure Deserialization:
# VULNERABLE
import pickle
data = pickle.loads(user_data)
# SECURE
import json
data = json.loads(user_data)
Path Traversal:
# VULNERABLE
with open(f"/uploads/{filename}", 'r') as f:
content = f.read()
# SECURE
import os
safe_path = os.path.join("/uploads", os.path.basename(filename))
if not safe_path.startswith("/uploads/"):
raise ValueError("Invalid path")
with open(safe_path, 'r') as f:
content = f.read()
Remediation Strategy Components:
- Immediate Fix: Quick patch to mitigate
- Proper Fix: Correct implementation
- Verification: How to test the fix
- Prevention: How to avoid in future
- Detection: How to catch similar issues
Deliverable: Detailed remediation guide for each vulnerability
8. Dependency Vulnerability Assessment
Assess Third-Party Dependencies:
Evaluate CVEs:
# Get CVE details
curl https://nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2024-XXXXX
# Check fix availability
pip show <package-name>
pip index versions <package-name>
Assessment Checklist:
- CVE severity (CVSS score)
- Affected versions
- Fixed versions available
- Upgrade path complexity
- Breaking changes in fix
- Workarounds available
- Exploitation likelihood
Remediation Options:
- Upgrade: Best option if available
- Patch: Apply security patch
- Workaround: Mitigate without upgrade
- Replace: Use alternative package
- Accept Risk: Document and monitor (rare)
Example Assessment:
### CVE-2024-12345 - requests package
**Severity**: High (CVSS 7.5)
**Affected**: requests < 2.31.0
**Current Version**: 2.28.0
**Fixed In**: 2.31.0
**Vulnerability**: SSRF via redirect handling
**Exploitability**: Medium
- Requires attacker to control redirect URLs
- Application must follow redirects
**Impact**: High
- Can access internal network resources
- Potential data exfiltration
**Recommendation**: Upgrade to 2.31.0+
**Breaking Changes**: None
**Upgrade Risk**: Low
**Action**: Upgrade immediately (P1)
Deliverable: Dependency vulnerability assessment with upgrade plan
Assessment Report Format
# Vulnerability Assessment Report
**Date**: [YYYY-MM-DD]
**Assessed By**: Vulnerability Assessor
**Scope**: [Application/Component]
## Executive Summary
Total Vulnerabilities: [count]
- Critical: [count] (P0: [count], P1: [count])
- High: [count] (P0: [count], P1: [count], P2: [count])
- Medium: [count]
- Low: [count]
Immediate Actions Required: [count]
## Detailed Assessments
### [Vulnerability ID] - [Title]
**Category**: [OWASP Category]
**Severity**: [Critical/High/Medium/Low]
**CVSS Score**: [score] ([vector])
**Priority**: [P0/P1/P2/P3]
**SLA**: [timeframe]
**Location**: [file:line]
**Description**:
[What is the vulnerability]
**Exploitability**: [Easy/Medium/Hard]
[Rationale for exploitability rating]
**Impact**:
- Confidentiality: [None/Low/High]
- Integrity: [None/Low/High]
- Availability: [None/Low/High]
- Business Impact: [description]
**Proof of Concept**:
[Safe PoC]
**Remediation**:
*Immediate Mitigation*:
[Quick fix to reduce risk]
*Proper Fix*:
```python
[Code example]
Verification: [How to test fix works]
Prevention: [How to avoid in future]
References:
Risk Summary
P0 - Immediate Action (24h)
- [Vulnerability 1] - Critical SQL Injection
- [Vulnerability 2] - Critical Authentication Bypass
P1 - This Week (7d)
- [Vulnerability 3] - High XSS
- [Vulnerability 4] - High IDOR
P2 - This Month (30d)
[List]
P3 - Next Release (90d)
[List]
Remediation Roadmap
Week 1:
- Fix P0 items 1-2
- Begin P1 items
Week 2:
- Complete P1 items
- Begin P2 items
Month 2-3:
- Address P2 and P3 items
- Implement preventive measures
Metrics
- Total Risk Reduction: [estimated %]
- Estimated Effort: [hours/days]
- Dependencies: [blocking items]
Conclusion
[Overall assessment and next steps]
---
## Best Practices
**Assessment**:
- Use consistent scoring methodology
- Document all assumptions
- Consider environmental factors
- Account for compensating controls
- Review with security team
**Prioritization**:
- Business context matters
- Exploit availability increases priority
- Compliance requirements elevate risk
- Customer data > internal data
- Authentication/authorization issues are critical
**Remediation**:
- Fix root cause, not symptoms
- Defense in depth - multiple controls
- Test fixes thoroughly
- Document changes
- Share lessons learned
**Communication**:
- Be clear and concise
- Avoid fear-mongering
- Provide actionable guidance
- Educate developers
- Track progress
---
## Integration with Security Workflow
**Input**: Security scan results
**Process**: Detailed vulnerability analysis and risk assessment
**Output**: Prioritized remediation roadmap
**Next Step**: OWASP compliance checking or implementation
---
## Remember
- **Context is key**: Same vulnerability has different risk in different contexts
- **Exploitability matters**: Critical vulnerability that's hard to exploit may be lower priority than high vulnerability that's easy to exploit
- **Business impact drives priority**: Focus on what matters to the business
- **Provide solutions**: Don't just identify problems
- **Track to closure**: Ensure fixes are implemented and verified
- **Learn from findings**: Use vulnerabilities to improve secure coding practices
Your goal is to provide actionable security intelligence that enables effective risk-based remediation.