Security is now VC due diligence. The term sheet depends on it.

Akande Simpa Lead Security Engineer & Cofounder, Simpa Labs CEH (Certified Ethical Hacker)

The technical diligence shift in Nigerian venture capital

Nigerian fintech startups used to follow a familiar playbook. They shipped features quickly and acquired users. They raised capital and planned to secure their systems later. This playbook failed. Over the last two years, multiple undisclosed payment platform hacks exposed logic flaws. These security failures drained between ₦50 million and ₦500 million in pre-seed and seed capital from newly funded accounts.

Because of these losses, institutional investors like Ventures Platform and Microtraction changed their technical due diligence checklists. Local syndicate leads did the same. They no longer write checks based on pitch decks and user growth metrics. Today, the signing of a term sheet marks the beginning of an intensive code and API review. Founders who treat security as a post-funding milestone find their deals stalled or cancelled at the final stage.

Anatomy of the exploit: Broken authorization on wallet transfers

Many early-stage payment platforms connect their backend systems to providers like Wema Bank and Providus Bank. They route transactions through Paystack or Flutterwave. However, the connection between these integrations often lacks strict access checks. A typical logic vulnerability involves Broken Object Level Authorization (BOLA) on wallet transfer endpoints.

An attacker registers a normal account and logs in. They capture an outgoing transaction request using Burp Suite. The outgoing HTTP request looks like this:

POST /api/v1/transfers HTTP/1.1
Host: api.staging.fintech.ng
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...
Content-Type: application/json

{
  "source_account_id": "wallet-9048-234",
  "destination_account_number": "0022334455",
  "destination_bank_code": "058",
  "amount_kobo": 25000000
}

The attacker changes source_account_id to wallet-8812-701, which belongs to another user. If the backend fails to check that the user in the JWT token owns the source account, the server authorizes the transaction. The platform communicates with the payment gateway to debit the victim's wallet. It then routes 250,000 Naira to the attacker's destination account. This attack bypasses standard authentication because the attacker's session token is valid. The system verifies who the caller is, but fails to check what resource they own.

The financial and regulatory toll of post-launch breaches

A post-launch security failure ruins your runway. The cost is not limited to the immediate cash stolen by attackers. If your platform exposes customer identity data or financial records, you trigger the Nigeria Data Protection Act (NDPA). The Nigeria Data Protection Commission (NDPC) penalizes major breaches with fines of up to ₦10 million or 2% of annual gross revenue.

The Central Bank of Nigeria (CBN) also enforces strict oversight. The regulator can suspend your Mobile Money Operator (MMO) or Payment Service Solution Provider (PSSP) operating license. They can disconnect your routing channels from NIBSS, bringing operations to a halt.

For startups in the middle of fundraising, a public breach or a poor diligence audit means VCs pull their term sheets immediately. Institutional partners will not disburse funds to a company with an active security risk. Your valuation drops, and the funding round collapses.

The components of modern VC technical diligence

When an investor audits your engineering assets, they look beyond simple code formatting. VCs partner with technical firms to inspect four areas:

• Proof of independent penetration testing: VCs require a recent Vulnerability Assessment and Penetration Testing (VAPT) report. The assessment must be performed by an accredited third-party security firm, not an internal team member.
• Core transaction logic reviews: Diligence partners trace how money flows through your code. They inspect how you authorize transaction actions. They check how you verify callbacks and how you check account balances.
• Verification of identity compliance: The review inspects how you integrate with identity vendors like Smile Identity or Dojah. They verify that your onboarding flows prevent BVN spoofing and bypass attempts.
• Secure secrets management: Technical auditors inspect your git history and deployment scripts. Hardcoded API keys or database credentials will halt the due diligence process.

The fundraising hazard of outsourced MVPs

Founders often build their Minimum Viable Products (MVPs) using external agencies or junior engineers. These teams prioritize user interfaces over security design. They build databases with default passwords and write APIs without authorization checks.

When the investor's technical partner reviews the repository, these shortcuts come to light. Finding hardcoded database passwords or missing database authorization filters stalls the deal. The investor must choose between walking away or demanding a lower valuation to offset the cost of rebuilding the security architecture. You lose time, and your funding round is delayed.

How to prepare your fintech for VC diligence

You must treat system security as a fundraising milestone. Do not wait for a Series A round to secure your ledger. Here is the process to fix these risks before talking to VCs:

First, secure your API endpoints with explicit database ownership checks. Use an ORM like Prisma to verify access in database transactions.

import { PrismaClient } from '@prisma/client';
const prisma = new PrismaClient();

// Authorization middleware verifies the user JWT token
export async function handleTransfer(req: Request, res: Response) {
  const userId = req.user.id; // Extracted from JWT context
  const { sourceAccountId, destinationAccount, bankCode, amountKobo } = req.body;

  try {
    const result = await prisma.$transaction(async (tx) => {
      // Fetch the source wallet using a database lock
      const wallet = await tx.wallet.findUnique({
        where: { id: sourceAccountId }
      });

      // Verify ownership on the server side
      if (!wallet || wallet.ownerId !== userId) {
        throw new Error('UNAUTHORIZED_WALLET_ACCESS');
      }

      // Check balance
      if (wallet.balanceKobo < amountKobo) {
        throw new Error('INSUFFICIENT_FUNDS');
      }

      // Debit the source wallet
      const updatedWallet = await tx.wallet.update({
        where: { id: sourceAccountId },
        data: { balanceKobo: { decrement: amountKobo } }
      });

      return updatedWallet;
    });

    // Proceed to trigger payment via Paystack or Flutterwave API
    return res.status(200).json({ success: true, balance: result.balanceKobo });
  } catch (error: any) {
    if (error.message === 'UNAUTHORIZED_WALLET_ACCESS') {
      return res.status(403).json({ error: 'Access denied' });
    }
    return res.status(400).json({ error: error.message });
  }
}

Second, set up a secure secrets architecture. Do not store live keys in your code repository or environment files. Move your production variables to a secret manager like Doppler or AWS Secrets Manager.

Third, run a focused API and authentication review before you open your public beta.

Fourth, compile a vendor security pack. This package should contain your NDA along with your VAPT certificate. It should also include a secure architecture brief. Providing this pack to investors during diligence shows operational maturity and keeps the deal moving.

Beyond automated scans

While automated tools scan for outdated dependencies, they cannot simulate the manual attack paths that due diligence partners use to find authorization bypasses in your custom transaction logic.

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