The risk profile of KYC data
Fintechs collect a staggering amount of sensitive data during onboarding: Bank Verification Numbers (BVNs), National Identity Numbers (NINs), government-issued IDs, and biometric facial scans. This data is highly liquid on the dark web because it enables comprehensive identity theft and account takeover across the entire financial ecosystem.
NDPA Compliance
The Nigeria Data Protection Act (NDPA) classifies much of this KYC data—especially biometrics—as Sensitive Personal Data, requiring stringent protection and explicit consent.
Insider Threat
A significant risk vector for BVN exposure is internal. Customer support or operations staff with over-permissioned access to administrative dashboards can exfiltrate identity data.
API Exposure
Poorly secured internal APIs or BOLA vulnerabilities can allow an attacker to enumerate and download KYC records for thousands of users.
Securing the identity pipeline
Encryption at rest and in transit
It is unacceptable to store BVNs, NINs, or cleartext ID document URLs in a database. Implement strong encryption at rest (e.g., AES-256) for the database columns storing these identifiers. Ensure that all transit, both externally to third-party providers and internally between microservices, is protected via TLS 1.2+.
Strict access logging and audit trails
Every time a staff member views a customer's KYC data, that action must be logged. The audit trail should record who accessed it, when, from what IP address, and the specific record viewed. This is critical for detecting insider threats and is a mandatory control reviewed during a CBN IT audit.
Data masking and least privilege
Customer support agents usually only need the last four digits of a BVN or NIN to verify a user. Implement data masking on internal dashboards so the full number is never displayed unless absolutely necessary, and only to authorized compliance personnel.
Are your KYC API endpoints exposing sensitive customer data?
Book an API Security TestSecuring third-party KYC integrations
Most Nigerian fintechs do not perform KYC entirely in-house; they rely on specialized providers like VerifyMe, Smile ID, or Youverify, which in turn connect to the NIBSS BVN Validation Service or NIMC.
- API Key Security: Store the API keys for your KYC providers in a secrets manager, not in your source code. If these keys are compromised, attackers can rack up massive API bills and potentially access your customers' verification history.
- Data Minimization: Only send the exact data required for verification. Do not pass unnecessary PII to the third-party provider.
- Vendor Due Diligence: Conduct regular vendor risk assessments on your KYC partners. Ensure they hold relevant certifications (ISO 27001, NDPC compliance) and review their incident response SLAs.
How pentests target KYC
During an assessment, our engineers specifically target the KYC upload and retrieval endpoints. We test for Broken Object Level Authorization (BOLA) to see if User A can view User B's uploaded ID document, and we attempt to upload malicious files (like malware disguised as an image) to test the robustness of the document processing pipeline.
Related reading
Blog: Why Nigerian Fintechs Are Targeted · NDPR Privacy Checklist
Guides: NDPR/NDPA Compliance Guide
Services: Authentication Security
Frequently asked questions
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