"Never trust the client. Never trust a supplied relationship. Never trust a supplied price. Never trust an authorization claim. Verify every security-critical invariant at the enforcement layer."

• We assume all browser environments (React state, localStorage, client memory, DevTools) are fully compromised or attacker-controlled.
• Prices, user roles, wallet identities, and permissions are never established by client declaration.
• Every economic transaction and permission claim is verified either:
  1. On-chain via the Solana Virtual Machine (SVM) program constraints; or
  2. Server-side via cryptographic signature verification against domain-bound nonces.

For every on-chain economic transfer: $$\text{creator_amount} + \text{treasury_fee} \equiv \text{total_payment}$$

• Single Source of Truth: The fee rate is dynamically retrieved from PlatformState.fee_bps. No constants are duplicated across instruction handlers.
• Bounded Fees: Maximum fee is hard-capped at 25.00% (MAX_FEE_BPS = 2_500).
• Mathematical Safety: Checked integer arithmetic prevents overflow and underflow across all amounts from 1 lamport to maximum safe u64.

• Never Trust Client Price: purchase_product reads product.price_lamports strictly from the on-chain Product account PDA derived from [b"product", creator, product_id].
• Creator Authorization: Only the authorized creator signer can create or modify products.
• Anti-Wash Trading Protection: The contract strictly disallows self-tipping (tipper != creator) and self-purchases (buyer != creator) to prevent artificial metric inflation and fake transaction volume.

• Two-Step Admin Transfer: Ownership transfers require initiation by current admin (transfer_admin), followed by explicit acceptance signature from the pending admin (accept_admin).
• Emergency Circuit Breaker: The platform can be paused by governance (pause_platform) to freeze all tips and purchases during security incidents while administrative recovery functions operate.
• Typed Account Validation: All creator and treasury destinations use typed SystemAccount<'info> with has_one constraints to eliminate account substitution attacks.

• Fail-Closed Secret Enforcement: SESSION_SECRET must be set with at least 32 characters in all environments; missing or short secrets trigger immediate fail-closed shutdown.
• Versioned HMAC Tokens: Stateless tamper-evident tokens using v1.<payloadBase64Url>.<signatureBase64Url> format signed with HMAC-SHA256 and constant-time crypto.timingSafeEqual comparison.
• Distributed State Coordination:
  • Single-Instance / Local Dev: High-performance in-memory Maps with sliding-window pruning, capacity bounds (MAX_ACTIVE_CHALLENGES = 10,000), and automatic expiration cleanup.
  • Multi-Instance / Serverless (Vercel): Zero-dependency REST adapter supporting Upstash Redis / Vercel KV for atomic single-use nonce consumption (GETDEL), cross-instance session revocation blocklists, and global rate limiting.

Permanent security regression tests are located under tests/security/:

• fee-invariant.test.mjs: Fuzzes 1,000 randomized amounts and boundary edge cases (1 lamport, 19 lamports, 100, 10,000, 1M COOK) confirming 100% preservation of the fee invariant.
• sanitize.test.mjs: Tests XSS payloads and SSRF vectors (cloud metadata, loopback, private IPv4 blocks).
• wallet-auth.test.mjs: Tests Ed25519 signature verification, nonce expiry, address mismatch rejection, and anti-replay nonce consumption.
• rate-limiter.test.mjs: Tests sliding-window quota enforcement and key isolation under simulated DoS traffic.
• session.test.mjs: Tests v1 token generation, tampering detection, fail-closed secrets, expiration, and authenticated revocation.
• contract-invariants.test.mjs: Tests anti-wash self-tipping rejection, self-purchase wash trading rejection, CEI ordering, and destination constraints.
• distributed-store.test.mjs: Tests atomic GETDEL nonce consumption, distributed TTL pruning, rate limiting increments, and REST protocol conformity.
• authorization.test.mjs: Tests multi-factor adulthood verification, role hierarchy, under-25 safeguards, and server-side feed shielding.
• trust-wallet-signer.test.mjs: Tests private key formats, SIWS challenge verification, and zero-leak platform administration controls.

Execute all suites locally with:

npm test

If you discover a security vulnerability, please do NOT create a public issue.

• Private Vulnerability Reporting: Enabled on this repository. Visit Security Advisories to submit a confidential report.
• Our security response team will review submissions promptly.