1. HIPAA Compliance Checklist

VitalNexa handles Protected Health Information (PHI) and is designed to comply with the HIPAA Privacy Rule and Security Rule. The following checklist tracks implementation status of required safeguards.

1.1 Administrative Safeguards

Requirement	Implementation	Status
Security Management Process	Risk analysis conducted; security policies documented; this security plan maintained	Complete
Assigned Security Responsibility	Security lead designated; responsibilities documented in team charter	Complete
Workforce Security	Role-based access; principle of least privilege; background checks for team members with PHI access	Complete
Security Awareness Training	Annual HIPAA training for all team members; phishing simulation exercises	Complete
Contingency Plan	Data backup procedures, disaster recovery plan, emergency mode operation plan	In Progress

1.2 Technical Safeguards

Requirement	Implementation	Status
Access Controls	JWT authentication with bcrypt password hashing; RBAC for user vs admin roles; session timeout after inactivity	Complete
Audit Controls	HIPAA middleware logs every API request with user_id, action, timestamp, IP, status code, response time	Complete
Integrity Controls	AES-256-GCM authenticated encryption prevents tampering; database constraints enforce data validity	Complete
Transmission Security	TLS 1.3 enforced for all connections; HSTS header with 1-year max-age; certificate pinning in mobile	Complete
Encryption at Rest	AES-256-GCM field-level encryption for all PII; database volume encryption; encrypted backups	Complete

1.3 Physical Safeguards

Requirement	Implementation	Status
Facility Access Controls	Cloud-hosted infrastructure (no physical servers); cloud provider SOC 2 Type II certified	Complete
Workstation Security	Full-disk encryption required; screen lock after 5 minutes; VPN for database access	Complete
Device and Media Controls	No PHI on portable devices; encrypted backups only; secure disposal procedures	Complete

2. Encryption Architecture

2.1 Field-Level Encryption (AES-256-GCM)

All PII fields are encrypted at the application layer before being written to PostgreSQL. This provides defense-in-depth beyond database-level encryption, ensuring that a database compromise alone does not expose sensitive data.

• Algorithm: AES-256-GCM (Galois/Counter Mode) providing both confidentiality and authenticity
• Key Length: 256-bit encryption keys derived from a master key using HKDF
• IV/Nonce: 96-bit random nonce generated per encryption operation (never reused)
• Authentication Tag: 128-bit GCM tag appended to ciphertext to detect tampering
• Encrypted Fields: Full name, date of birth, email address, health record content, uploaded file content

2.2 Key Management

Aspect	Implementation
Key Storage	Master key stored in environment variable, never committed to source control. Production uses cloud KMS.
Key Versioning	Each encryption stores the key version alongside ciphertext. Format: v{version}:{iv}:{ciphertext}:{tag}
Key Rotation	New key version generated quarterly. Old keys retained for decryption. Background job re-encrypts records to latest version.
Key Derivation	Per-field keys derived from master key using HKDF-SHA256 with field-specific context strings.
Emergency Revocation	Procedure to revoke a compromised key version and trigger immediate re-encryption of all affected records.

2.3 Encryption in Transit

• TLS 1.3 required for all client-server communication
• TLS 1.2 with strong cipher suites accepted as fallback
• HSTS header enforced with max-age=31536000; includeSubDomains
• Database connections use SSL with certificate verification
• Internal service-to-service calls use mTLS where applicable

3. Threat Model (OWASP Top 10)

OWASP Category	Risk Level	Mitigation	Status
A01: Broken Access Control	Critical	PostgreSQL RLS enforces tenant isolation at the database level. JWT claims validated on every request. API returns 404 (not 403) for cross-tenant resource access to prevent enumeration.	Mitigated
A02: Cryptographic Failures	Critical	AES-256-GCM for PII encryption. bcrypt with cost factor 12 for passwords. TLS 1.3 in transit. No sensitive data in logs or error messages.	Mitigated
A03: Injection	High	Parameterized queries via SQLAlchemy ORM. Pydantic input validation on all endpoints. No raw SQL construction from user input.	Mitigated
A04: Insecure Design	Medium	Threat modeling during design phase. Security requirements in PRD. Defense-in-depth architecture. AI guardrails prevent clinical diagnosis.	Mitigated
A05: Security Misconfiguration	Medium	Hardened default configurations. Security headers enforced. Debug mode disabled in production. Dependency scanning via Dependabot.	Mitigated
A06: Vulnerable Components	Medium	Automated dependency scanning. Weekly vulnerability report review. Pinned dependency versions with automated update PRs.	Mitigated
A07: Auth Failures	High	Account lockout after 5 failed attempts. JWT with short expiry. Refresh token rotation. Email verification required. Rate limiting on auth endpoints.	Mitigated
A08: Software/Data Integrity	Medium	CI/CD pipeline with signed commits. Dependency integrity verification. GCM authentication tags prevent data tampering.	Mitigated
A09: Logging Failures	Medium	HIPAA audit middleware logs all requests. Logs shipped to append-only storage. Alerting on anomalous patterns.	Mitigated
A10: SSRF	Low	No user-supplied URLs fetched by the server. File upload validates content type and restricts to .txt/.pdf. No external URL resolution.	Mitigated

4. Authentication Security

4.1 Password Policy

• Minimum 8 characters with uppercase, lowercase, digit, and special character
• Passwords hashed with bcrypt (cost factor 12, ~250ms per hash)
• Passwords checked against the Have I Been Pwned breach database
• No password hints or security questions

4.2 Account Lockout

• 5 consecutive failed login attempts trigger a 30-minute lockout
• Lockout counter tracked per account, not per IP (prevents IP rotation bypass)
• Counter resets on successful login
• Lockout events logged for security monitoring

4.3 Token Security

• Access tokens: 15-minute expiry, signed with HS256 using a 256-bit secret
• Refresh tokens: 7-day expiry, single-use (rotated on each refresh)
• Tokens stored in httpOnly, Secure, SameSite=Strict cookies (not localStorage)
• Token revocation list checked on every authenticated request

5. Data Isolation and Multi-Tenancy

VitalNexa uses PostgreSQL Row-Level Security (RLS) to enforce strict data isolation between users. Every table containing user data has RLS policies that filter rows based on the authenticated user's ID, set at the database session level.

• RLS policies are FORCE enabled, meaning they apply even to table owners
• The application sets app.current_user_id on each database session before executing queries
• All SELECT, INSERT, UPDATE, and DELETE operations are filtered by the RLS policy
• Integration tests verify isolation by attempting cross-tenant queries and asserting zero results
• Database migrations include RLS policy creation as part of table creation

6. Audit Logging

HIPAA requires comprehensive audit trails for all access to PHI. VitalNexa implements this through FastAPI middleware that logs every request.

6.1 Audit Log Fields

Field	Description	Example
timestamp	ISO 8601 timestamp of the request	2026-04-05T14:32:01.445Z
user_id	Authenticated user's UUID (null for unauthenticated requests)	a1b2c3d4-e5f6-7890-abcd-ef1234567890
action	HTTP method and path	GET /api/test-results
ip_address	Client IP (respects X-Forwarded-For behind load balancer)	203.0.113.42
status_code	HTTP response status code	200
response_time_ms	Request processing time in milliseconds	45
resource_id	ID of the accessed resource (if applicable)	record-uuid-here
user_agent	Client user-agent string	Mozilla/5.0...

6.2 Log Integrity

• Audit logs are written to an append-only table with no UPDATE or DELETE permissions
• Logs are replicated to a separate, read-only storage location daily
• Retention policy: minimum 6 years per HIPAA requirements
• Anomaly detection alerts on unusual access patterns (e.g., bulk data access, off-hours activity)

7. Incident Response Plan

7.1 Severity Levels

Severity	Definition	Response Time	Examples
P1 - Critical	Active data breach or PHI exposure	Immediate (within 15 minutes)	Unauthorized PHI access, encryption key compromise, active exploitation
P2 - High	Vulnerability with high exploitation potential	Within 4 hours	Auth bypass discovered, RLS policy gap, unpatched critical CVE
P3 - Medium	Security issue with limited exposure	Within 24 hours	Missing security header, minor information disclosure, failed pen test finding
P4 - Low	Hardening opportunity, no active risk	Within 1 week	Dependency update available, log verbosity reduction, documentation gap

7.2 Response Procedure

1. Detection: Automated monitoring, audit log alerts, user reports, or security scans identify the incident
2. Containment: Immediately isolate affected systems; revoke compromised credentials; block attacker IPs
3. Assessment: Determine scope of data exposure; identify affected users; preserve forensic evidence
4. Notification: If PHI is breached, notify affected individuals within 60 days per HIPAA Breach Notification Rule; notify HHS if 500+ individuals affected
5. Remediation: Patch the vulnerability; rotate affected keys/credentials; deploy fixes
6. Post-Mortem: Conduct blameless post-mortem within 5 business days; document root cause, timeline, and preventive measures

8. Regulatory Alignment

VitalNexa's security architecture is designed to meet or exceed the requirements of major health data and privacy regulations:

Regulation	Scope	Our Alignment
HIPAA / HITECH	US health data protection	HIPAA-grade safeguards including AES-256-GCM encryption at rest, TLS 1.3 in transit, comprehensive audit logging, breach notification procedures, and Business Associate Agreements with all third-party processors
GDPR	EU/EEA data subject rights	Full data subject rights support: access, rectification, erasure, portability (JSON export), restriction of processing, right to object, and withdrawal of consent. Data processing based on explicit consent, legitimate interest, and contractual necessity. 72-hour breach notification to supervisory authorities.
CCPA / CPRA	California consumer rights	Right to know, right to delete, right to opt-out of sale (we never sell data), right to non-discrimination, and right to correct. See our Do Not Sell page.

For complete details on data handling practices and user rights, see our Privacy Policy. For breach notification procedures including GDPR 72-hour requirements, see our Incident Response Policy.

9. OWASP Top 10 Audit

• Critical findings (2): Broken Access Control hardening and Cryptographic Failures review — both fully resolved
• High findings (2): SQL Injection prevention validation and Authentication Failures hardening — both fully resolved
• Medium findings (4): Insecure Design patterns, Security Misconfiguration, Vulnerable Components, and Software/Data Integrity — all fully resolved
• Low findings (2): Logging enhancement and SSRF edge cases — accepted with compensating controls
• Test coverage: 325+ automated tests across 26 test files (~4,700 lines of test code) validate security controls

10. Security Assessment Status

Assessment Area	Last Assessed	Findings	Status
OWASP ZAP Baseline Scan	March 28, 2026	0 high, 2 medium (resolved), 4 low (accepted)	Pass
Dependency Vulnerability Scan	April 3, 2026	0 critical, 0 high, 1 medium (upgrade scheduled)	Pass
RLS Isolation Audit	April 1, 2026	All tables verified; no cross-tenant data access possible	Pass
Encryption Implementation Review	March 25, 2026	AES-256-GCM correctly implemented; key rotation tested; no issues found	Pass
OWASP Top 10 Audit	April 2026	All 10 categories assessed; all Critical/High/Medium findings remediated	Pass
Penetration Test (External)	Scheduled	Planned for Q2 2026 prior to public launch	Pending
SOC 2 Type II Audit	Scheduled	Planned for Q4 2026	Pending
HIPAA Risk Assessment	March 15, 2026	Initial assessment complete; 3 remediation items addressed	Pass
Data Backup and Recovery Test	March 20, 2026	Full restore completed in 47 minutes; RPO and RTO targets met	Pass