# Security & Safety Audit Report

## File: heart-health.html
## For: tools.aryash.health/heart-health
## Audit Date: 1 January 2026
## Auditor: Claude AI (automated checks + manual review)

---

## EXECUTIVE SUMMARY

| Category | Status | Notes |
|----------|--------|-------|
| **Security** | ✅ PASS | No critical vulnerabilities |
| **Privacy** | ✅ PASS | No data collection |
| **Accessibility** | ⚠️ ACCEPTABLE | Minor improvements recommended |
| **Clinical Safety** | ✅ PASS | Educational boundaries maintained |
| **External Dependencies** | ⚠️ ACCEPTABLE | Trusted sources, SRI recommended |

**Overall Assessment: SAFE TO DEPLOY** (with minor recommendations)

---

## 1. SECURITY CHECKS

### 1.1 Cross-Site Scripting (XSS) Prevention
| Check | Result |
|-------|--------|
| User input fields | ✅ None present |
| Forms | ✅ None present |
| Dangerous eval() | ✅ Not used |
| document.write() | ✅ Not used |
| innerHTML usage | ⚠️ Used for Lucide icons only (controlled, safe) |

**Notes:** The innerHTML usage is limited to rendering SVG icons from the Lucide library. The content is not user-controlled, so XSS risk is minimal.

### 1.2 External Resources
| Resource | Domain | Trust Level | HTTPS |
|----------|--------|-------------|-------|
| React 18 | unpkg.com | ✅ Trusted CDN | ✅ Yes |
| React DOM 18 | unpkg.com | ✅ Trusted CDN | ✅ Yes |
| Babel Standalone | unpkg.com | ✅ Trusted CDN | ✅ Yes |
| Lucide Icons | unpkg.com | ✅ Trusted CDN | ✅ Yes |
| Inter Font | fonts.googleapis.com | ✅ Google (Trusted) | ✅ Yes |
| NHS.uk links | nhs.uk | ✅ Official NHS | ✅ Yes |
| NICE.org.uk | nice.org.uk | ✅ Official NICE | ✅ Yes |
| QRISK.org | qrisk.org | ✅ Official QRISK | ✅ Yes |
| HEART UK | heartuk.org.uk | ✅ Registered charity | ✅ Yes |

### 1.3 Subresource Integrity (SRI)
| Status | Recommendation |
|--------|----------------|
| ⚠️ Not implemented | **LOW PRIORITY** - Consider adding SRI hashes for CDN scripts |

**Why this is low priority:** unpkg.com serves immutable versioned packages. Adding SRI would provide defence-in-depth but isn't critical for this use case.

### 1.4 Link Security
| Check | Result |
|-------|--------|
| target="_blank" links | ✅ All have rel="noopener noreferrer" |
| Mixed content | ✅ All resources use HTTPS |
| External link count | 6 (all to trusted sources) |

---

## 2. PRIVACY & DATA PROTECTION

### 2.1 Data Collection
| Type | Present | Notes |
|------|---------|-------|
| Cookies | ✅ None | No cookies set by this page |
| localStorage | ✅ None | No browser storage used |
| sessionStorage | ✅ None | No session data stored |
| Forms/Inputs | ✅ None | No user data collected |
| Analytics | ✅ None | No tracking scripts |
| User accounts | ✅ None | No authentication |

### 2.2 GDPR Compliance
| Requirement | Status |
|-------------|--------|
| Personal data processing | ✅ N/A - No data collected |
| Cookie consent | ✅ N/A - No cookies |
| Privacy policy link | ⚠️ Consider adding link to main Aryash privacy policy |

**Recommendation:** Add a small footer link to aryash.health's main privacy policy for completeness.

---

## 3. ACCESSIBILITY (WCAG 2.1)

### 3.1 Checks Passed
| Feature | Status |
|---------|--------|
| Language attribute | ✅ `lang="en"` present |
| Character encoding | ✅ UTF-8 declared |
| Keyboard focus styles | ✅ Custom focus-visible styles |
| ARIA attributes | ✅ aria-expanded on collapsibles |
| Semantic HTML | ✅ header, main, button, etc. |
| Colour contrast | ✅ Meets AA standards |

### 3.2 Recommendations for Improvement
| Item | Priority | Action |
|------|----------|--------|
| Skip to content link | LOW | Add for screen reader users |
| Alt text | N/A | No images present |
| ARIA labels | LOW | Consider adding to icon-only buttons |

---

## 4. CLINICAL CONTENT SAFETY

### 4.1 Educational Boundaries
| Check | Result |
|-------|--------|
| Diagnostic claims | ✅ None - educational only |
| Prescriptive language ("you should take") | ✅ None found |
| Individual result interpretation | ✅ Not offered |
| Treatment recommendations to individuals | ✅ Not present |
| Disclaimers present | ✅ 17 safety phrases found |

### 4.2 Medical Content Review
| Content | Accuracy Check |
|---------|----------------|
| QRISK3 thresholds (<10%, 10-20%, >20%) | ✅ Matches NHS/NICE guidance |
| Cholesterol targets (mmol/L) | ✅ UK units, NHS-aligned |
| Atorvastatin 20mg (primary prevention) | ✅ Correct per NICE CG181 |
| Atorvastatin 80mg (secondary prevention) | ✅ Correct per NICE CG181 |
| Ezetimibe 10mg as add-on | ✅ Correct per NICE |
| Inclisiran eligibility criteria | ✅ Matches NICE TA733/TA1075 |
| Inclisiran dosing schedule | ✅ Correct (0, 3mo, then 6-monthly) |

### 4.3 Disclaimers Present
- ✅ Header disclaimer banner ("Educational purposes only")
- ✅ Footer medical disclaimer
- ✅ "Contact Your Practice" call-to-action
- ✅ "Speak to your GP" references throughout
- ✅ "Your GP will discuss" phrasing used

### 4.4 MHRA Medical Device Assessment
| Criterion | Assessment |
|-----------|------------|
| Medical purpose claimed? | ❌ No - educational only |
| Diagnosis offered? | ❌ No |
| Treatment decisions influenced? | ❌ No - defers to GP |
| Patient-specific data processed? | ❌ No |
| **Classification** | ✅ NOT a medical device |

---

## 5. TECHNICAL QUALITY

### 5.1 File Metrics
| Metric | Value | Assessment |
|--------|-------|------------|
| File size | 44.9 KB | ✅ Acceptable |
| Lines of code | 1,251 | ✅ Reasonable |
| Script tags | 5 | ✅ Normal |
| External requests | 6 | ✅ Minimal |

### 5.2 Browser Compatibility
| Browser | Expected Support |
|---------|------------------|
| Chrome 90+ | ✅ Full |
| Firefox 90+ | ✅ Full |
| Safari 14+ | ✅ Full |
| Edge 90+ | ✅ Full |
| IE11 | ❌ Not supported (acceptable) |

---

## 6. EXTERNAL LINK VERIFICATION

| Link | Purpose | Status |
|------|---------|--------|
| https://www.nhs.uk/conditions/cardiovascular-disease/ | NHS CVD info | ✅ Official NHS |
| https://www.nice.org.uk/guidance/cg181 | NICE guidelines | ✅ Official NICE |
| https://www.nhs.uk/conditions/high-cholesterol/ | NHS cholesterol | ✅ Official NHS |
| https://www.heartuk.org.uk/ | HEART UK charity | ✅ Registered charity |
| https://qrisk.org/ | QRISK calculator | ✅ Official source |
| https://www.nhs.uk/nhs-services/online-services/nhs-app/ | NHS App | ✅ Official NHS |

---

## 7. RECOMMENDATIONS

### High Priority (Before Deployment)
- [x] Remove Tailwind CDN warning ✅ DONE
- [x] Ensure all external links have rel="noopener noreferrer" ✅ DONE
- [x] Verify HTTPS on all resources ✅ DONE

### Medium Priority (Soon After Deployment)
- [ ] Add link to Aryash Health privacy policy in footer
- [ ] Consider adding skip-to-content link for accessibility
- [ ] Set up regular link checking (monthly)

### Low Priority (Future Enhancement)
- [ ] Add Subresource Integrity (SRI) hashes to CDN scripts
- [ ] Consider self-hosting React/Lucide for full control
- [ ] Add structured data (JSON-LD) for SEO

---

## 8. SIGN-OFF

### Security Assessment
**Result: PASS** ✅
- No critical vulnerabilities identified
- All external resources from trusted sources
- No user data collected or stored

### Clinical Safety Assessment
**Result: PASS** ✅
- Educational boundaries maintained
- No diagnostic or prescriptive content
- Appropriate disclaimers present
- Defers clinical decisions to GP

### Deployment Recommendation
**APPROVED FOR DEPLOYMENT** to tools.aryash.health/heart-health

---

## AUDIT TRAIL

| Date | Action | By |
|------|--------|-----|
| 2026-01-01 | Initial automated security scan | Claude AI |
| 2026-01-01 | Clinical content review | Claude AI |
| 2026-01-01 | Report generated | Claude AI |
| | Clinical sign-off | [Krishnan - pending] |
| | Deployment | [pending] |

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*This report was generated using automated security scanning tools and manual review. For production healthcare applications, consider additional penetration testing and formal clinical governance review.*