Fintech Startup Network Security Assessment

Client Overview

A fintech startup preparing for Series A due diligence needed to demonstrate a secure network posture. They had limited internal security resources and required a focused network security assessment with clear remediation support.

Industry: Financial Services / Fintech
Challenge: Identify exposed services, misconfigurations, and firewall gaps before investor review
Engagement: 2 weeks (scoping, scan, report, remediation support)

Scoping & Requirements

Scope: Internet-facing IP ranges, cloud VPCs (AWS), and internal segments used for development and staging.

Success criteria: No critical/high exposure from internet; firewall rules documented and tightened. Rules of engagement: scanning from approved IPs; no exploitation; coordination with cloud provider.

Methodology & Test Cases

Port scanning, service enumeration, banner grabbing, and firewall rule analysis. Test cases included: full port scan (TCP/UDP key ports), service identification and CVE mapping, firewall and security group review, network segmentation validation.

Phase	Activities
Discovery	Nmap, masscan; asset inventory reconciliation
Vulnerability	OpenVAS/Nessus for identified services; SSL/TLS checks
Firewall	Rule review, least-privilege recommendations

Tools: Nmap, OpenVAS, custom scripts. Standards: CIS benchmarks, NIST.

Findings & Remediation

28 findings (4 critical, 9 high, 10 medium, 5 low). Critical: exposed RDP and database port on a misconfigured bastion; over-permissive security groups allowing 0.0.0.0/0 to app tier. We provided rule changes and architecture recommendations; client implemented fixes and we retested.

Results & Impact

            All critical and high findings remediated within 10 days.
88% risk reduction; internet attack surface reduced significantly.
Due diligence questionnaire completed with confidence; Series A proceeded.

        

"Fast, thorough, and helped us secure our network before our Series A due diligence."

— CTO, Fintech Startup

Key Takeaways

Clear scope and success criteria aligned to due diligence sped up the engagement. For similar startups: include cloud security groups and NACLs in scope; plan one retest cycle; document compensating controls for any accepted risk.