Healthcare Web & API Pentest
European Healthcare Platform - Patient Data Protection
In-depth security assessment of a European healthcare platform handling sensitive patient data. Identified 5 vulnerabilities across authentication, authorization, and business logic layers, with a prioritized remediation roadmap delivered within a 3-week engagement.
Project Overview
Industry
Healthcare
Test Type
Web & API Grey-box Test
Duration
3 weeks
Challenges & Objectives
Challenge
A healthcare platform processing sensitive patient data across European markets required rigorous security validation to meet regulatory requirements and protect against unauthorized access to medical records and appointment systems.
Objectives
- Assess authentication and authorization mechanisms across all API endpoints
- Identify business logic flaws in scheduling, account management, and data access workflows
- Validate rate-limiting and brute-force protections on critical authentication flows
- Ensure compliance readiness for European healthcare data protection standards
Methodology
API Mapping
Comprehensive enumeration of all API endpoints, authentication flows, and data access patterns
Auth & Access Testing
Systematic testing of authentication bypasses, OTP mechanisms, and object-level access controls
Business Logic Analysis
Manual testing of scheduling workflows, state transitions, and feature toggle enforcement
Remediation Roadmap
Prioritized findings with severity-based remediation plan and verification retesting
Key Findings (5 vulnerabilities)
No Rate-Limiting on OTP Verification
The OTP verification endpoint lacked rate-limiting controls, allowing unlimited brute-force attempts to guess one-time passwords and bypass two-factor authentication.
Recommendation
Implement strict rate-limiting (maximum 3-5 attempts) and temporary lockouts for OTP verification.
Missing Authentication on API Endpoints
Several API endpoints were accessible without any authentication checks, exposing sensitive patient data and administrative functions to unauthenticated users.
Recommendation
Enforce authentication checks on all API endpoints by default.
Improper Authorization - Broken Object-Level Access Control (CWE-285)
Authenticated users could access and modify resources belonging to other users by manipulating object identifiers in API requests.
Recommendation
Implement robust server-side Object-Level Access Control on all data operations.
Race Condition in Schedule Creation
Concurrent requests to the scheduling endpoint could bypass availability checks, allowing double-booking and conflicting appointment slots.
Recommendation
Implement database transaction locks or mutual exclusion mechanisms to process schedule creation requests sequentially.
Business Logic Errors
Multiple business rules, state validations, and feature toggles were only enforced client-side, allowing attackers to bypass restrictions via direct API calls.
Recommendation
Enforce all business logic rules, state validations, and feature toggles strictly on the server-side.
Value Delivered
Patient Data Protection
Identified and remediated critical access control flaws protecting sensitive medical records
Regulatory Compliance
Strengthened security posture for European healthcare data protection requirements
Prioritized Remediation
Delivered severity-based remediation roadmap with all issues fixed during the engagement