Secure Financial App on Shared Server

Project Description:
I need an experienced cybersecurity specialist to review and secure my finance application hosted on a shared server. The app handles sensitive financial data, so I need help with:

1. Security Audit (Check for vulnerabilities like SQLi, XSS, misconfigurations)
2. Compliance Guidance (GDPR, PCI DSS if applicable)
3. Server Hardening (Shared hosting risks, firewall rules, encryption)
4. Secure Authentication (MFA implementation, session management)
5. Code Review (Check for backdoors, insecure APIs, hardcoded secrets)
6. Penetration Testing (Simulate attacks to find weaknesses)

Requirements:
Proven experience in securing financial/web applications
Knowledge of OWASP Top 10, GDPR, PCI DSS (when payments are processed)
Ability to provide clear recommendations & fixes
Experience with shared hosting security limitations
Preferred Qualifications (Bonus):
Certifications like CEH, CISSP, OSCP
Experience with Cloudflare, WAFs, SIEM tools
Knowledge of .NET (since servers uses Windows hosting)