wifi-densepose/examples/edge-net/docs/SECURITY_AUDIT_REPORT.md

Edge-Net Relay Security Audit Report

Date: 2026-01-03 Auditor: Code Review Agent Component: Edge-Net WebSocket Relay Server (/relay/index.js) Version: v0.1.0

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Executive Summary

A comprehensive security audit was conducted on the Edge-Net relay server, focusing on authentication, authorization, and protection against common attack vectors. The relay implements strong security controls for task assignment and credit distribution, with Firestore-backed QDAG (Quantum Directed Acyclic Graph) ledger as the source of truth.

Overall Security Rating: ✅ GOOD (with minor recommendations)

Key Findings

Category	Status	Details
Task Completion Spoofing	✅ SECURE	Protected by assignment tracking
Replay Attacks	✅ SECURE	Protected by completed tasks set
Credit Self-Reporting	✅ SECURE	Disabled - relay-only crediting
Public Key Spoofing	⚠️ MOSTLY SECURE	See recommendations
Rate Limiting	✅ IMPLEMENTED	Per-node message throttling
Message Size Limits	✅ IMPLEMENTED	64KB max payload
Connection Limits	✅ IMPLEMENTED	5 connections per IP
Origin Validation	✅ IMPLEMENTED	CORS whitelist

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Security Architecture

1. QDAG Ledger (Source of Truth)

Implementation: Lines 66-142

// Firestore-backed persistent credit ledger
const ledgerCollection = firestore.collection('edge-net-qdag');

// Credits ONLY increase via verified task completions
async function creditAccount(publicKey, amount, taskId) {
  const ledger = await loadLedger(publicKey);
  ledger.earned += amount;
  ledger.tasksCompleted += 1;
  await saveLedger(publicKey, ledger);
}

Security Properties:

• ✅ Credits keyed by public key (identity-based, not node-based)
• ✅ Persistent across sessions (Firestore)
• ✅ Server-side only (clients cannot modify)
• ✅ Atomic operations with in-memory cache

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Attack Vector Analysis

🔴 Attack Vector 1: Task Completion Spoofing

Description: Malicious node tries to complete tasks not assigned to them.

Protection Mechanism (Lines 61-64, 222-229, 411-423):

// Track assigned tasks with assignment metadata
const assignedTasks = new Map(); // taskId -> { assignedTo, submitter, maxCredits }

// On task assignment (lines 222-229)
assignedTasks.set(task.id, {
  assignedTo: targetNodeId,
  assignedToPublicKey: targetWs.publicKey,
  submitter: task.submitter,
  maxCredits: task.maxCredits,
  assignedAt: Date.now(),
});

// On task completion (lines 411-423)
const assignment = assignedTasks.get(taskId);
if (!assignment) {
  console.warn(`Task ${taskId} not found or expired`);
  ws.send(JSON.stringify({ type: 'error', message: 'Task not found or expired' }));
  break;
}

if (assignment.assignedTo !== nodeId) {
  console.warn(`Task ${taskId} assigned to ${assignment.assignedTo}, not ${nodeId} - SPOOFING ATTEMPT`);
  ws.send(JSON.stringify({ type: 'error', message: 'Task not assigned to you' }));
  break;
}

Security Assessment: ✅ SECURE

• Assignment tracked with node ID verification
• Only assigned node can complete task
• Clear error messages for debugging (but could be more generic for production)

Test Coverage: relay-security.test.ts - "Task Completion Spoofing" suite

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🔴 Attack Vector 2: Replay Attacks

Description: Malicious node tries to complete the same task multiple times to earn duplicate credits.

Protection Mechanism (Lines 64, 425-430, 441):

const completedTasks = new Set(); // Prevent double completion

// On task completion (lines 425-430)
if (completedTasks.has(taskId)) {
  console.warn(`Task ${taskId} already completed - REPLAY ATTEMPT from ${nodeId}`);
  ws.send(JSON.stringify({ type: 'error', message: 'Task already completed' }));
  break;
}

// Mark completed BEFORE crediting (line 441)
completedTasks.add(taskId);
assignedTasks.delete(taskId);

Security Assessment: ✅ SECURE

• Tasks marked complete before crediting (prevents race conditions)
• Permanent replay prevention (Set-based tracking)
• Assignment deleted after completion

Potential Issue: ⚠️ completedTasks Set grows unbounded

Recommendation: Implement periodic cleanup for old completed tasks:

// Cleanup completed tasks older than 24 hours
setInterval(() => {
  const CLEANUP_AGE = 24 * 60 * 60 * 1000; // 24 hours
  // Track completion timestamps and remove old entries
}, 60 * 60 * 1000); // Every hour

Test Coverage: relay-security.test.ts - "Replay Attacks" suite

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🔴 Attack Vector 3: Credit Self-Reporting

Description: Malicious client tries to submit their own credit values to inflate balance.

Protection Mechanism (Lines 612-622):

case 'ledger_update':
  // DEPRECATED: Clients cannot self-report credits
  {
    console.warn(`[QDAG] REJECTED ledger_update from ${nodeId} - clients cannot self-report credits`);
    ws.send(JSON.stringify({
      type: 'error',
      message: 'Credit self-reporting disabled. Credits earned via task completions only.',
    }));
  }
  break;

Security Assessment: ✅ SECURE

• ledger_update messages explicitly rejected
• Only creditAccount() function can increase earned credits
• creditAccount() only called after verified task completion (lines 450-451)
• Firestore ledger is source of truth

Additional Security:

• ledger_sync is read-only (lines 570-610) - returns balance from Firestore
• No client-submitted credit values accepted anywhere

Test Coverage: relay-security.test.ts - "Credit Self-Reporting" suite

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🔴 Attack Vector 4: Public Key Spoofing

Description: Malicious node tries to use another user's public key to claim their credits or identity.

Protection Mechanism: Lines 360-366, 432-438, 584

Current Implementation:

// On registration (lines 360-366)
if (message.publicKey) {
  ws.publicKey = message.publicKey;
  console.log(`Node registered: ${nodeId} with identity ${message.publicKey.slice(0, 16)}...`);
}

// On task completion (lines 432-438)
const processorPublicKey = assignment.assignedToPublicKey || ws.publicKey;
if (!processorPublicKey) {
  ws.send(JSON.stringify({ type: 'error', message: 'Public key required for credit' }));
  break;
}

// Credits go to the PUBLIC KEY stored in assignment
await creditAccount(processorPublicKey, rewardRuv, taskId);

Security Assessment: ⚠️ MOSTLY SECURE (with caveats)

What IS Secure:

• ✅ Credits keyed by public key (same identity = same balance everywhere)
• ✅ Public key stored at assignment time (prevents mid-flight changes)
• ✅ Credits awarded to assignment.assignedToPublicKey (not current ws.publicKey)
• ✅ Multiple nodes can share public key (multi-device support by design)

What IS NOT Fully Protected:

• ⚠️ No cryptographic signature verification (Line 281-286)

// CURRENT: Placeholder validation
function validateSignature(nodeId, message, signature, publicKey) {
  // In production, verify Ed25519 signature from PiKey
  // For now, accept if nodeId matches registered node
  return nodes.has(nodeId);
}

• ⚠️ Clients can claim any public key without proving ownership
• ⚠️ This allows "read-only spoofing" - checking another user's balance

Impact Assessment:

Scenario	Risk Level	Impact
Checking another user's balance	🟡 LOW	Privacy leak, but no financial impact
Claiming another user's public key at registration	🟡 LOW	Cannot steal existing credits (assigned at task time)
Earning credits to someone else's key	🟡 LOW	Self-harm (attacker works for victim's benefit)
Completing tasks assigned to victim	🔴 NONE	Protected by assignedTo node ID check

Recommendations:

1. Implement Ed25519 Signature Verification (CRITICAL for production):

import { verify } from '@noble/ed25519';

async function validateSignature(message, signature, publicKey) {
  try {
    const msgHash = createHash('sha256').update(JSON.stringify(message)).digest();
    return await verify(signature, msgHash, publicKey);
  } catch {
    return false;
  }
}

// Require signature on sensitive operations
case 'task_complete':
  if (!message.signature || !validateSignature(message, message.signature, ws.publicKey)) {
    ws.send(JSON.stringify({ type: 'error', message: 'Invalid signature' }));
    break;
  }
  // ... rest of task completion logic

2. Add Challenge-Response on Registration:

case 'register':
  // Send challenge
  const challenge = randomBytes(32).toString('hex');
  challenges.set(nodeId, challenge);
  ws.send(JSON.stringify({
    type: 'challenge',
    challenge: challenge,
  }));
  break;

case 'challenge_response':
  const challenge = challenges.get(nodeId);
  if (!validateSignature({ challenge }, message.signature, message.publicKey)) {
    ws.close(4003, 'Invalid signature');
    break;
  }
  // Complete registration...

3. Rate-limit balance queries to prevent enumeration attacks:

case 'ledger_sync':
  if (!checkRateLimit(`${nodeId}-ledger-sync`, 10, 60000)) { // 10 per minute
    ws.send(JSON.stringify({ type: 'error', message: 'Balance query rate limit' }));
    break;
  }

Test Coverage: relay-security.test.ts - "Public Key Spoofing" suite

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Additional Security Features

5. Rate Limiting

Implementation: Lines 45-46, 265-279, 346-350

const rateLimits = new Map();
const RATE_LIMIT_MAX = 100; // max messages per window
const RATE_LIMIT_WINDOW = 60000; // 1 minute

function checkRateLimit(nodeId) {
  const now = Date.now();
  const limit = rateLimits.get(nodeId) || { count: 0, windowStart: now };

  if (now - limit.windowStart > RATE_LIMIT_WINDOW) {
    limit.count = 0;
    limit.windowStart = now;
  }

  limit.count++;
  rateLimits.set(nodeId, limit);

  return limit.count <= RATE_LIMIT_MAX;
}

Security Assessment: ✅ GOOD

• Per-node rate limiting (not global)
• Sliding window implementation
• Enforced after registration

Recommendations:

• ✅ Consider adaptive rate limits based on node reputation
• ✅ Add separate limits for expensive operations (task_submit, ledger_sync)

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6. Message Size Limits

Implementation: Lines 21, 318, 338-342

const MAX_MESSAGE_SIZE = 64 * 1024; // 64KB

ws._maxPayload = MAX_MESSAGE_SIZE;

if (data.length > MAX_MESSAGE_SIZE) {
  ws.send(JSON.stringify({ type: 'error', message: 'Message too large' }));
  return;
}

Security Assessment: ✅ GOOD

• Prevents DoS via large payloads
• Enforced at both WebSocket and application layer
• 64KB is reasonable for control messages

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7. Connection Limits

Implementation: Lines 22, 308-315, 671-677

const MAX_CONNECTIONS_PER_IP = 5;
const ipConnections = new Map();

// On connection
const ipCount = ipConnections.get(clientIP) || 0;
if (ipCount >= MAX_CONNECTIONS_PER_IP) {
  console.log(`Rejected connection: too many from ${clientIP}`);
  ws.close(4002, 'Too many connections');
  return;
}
ipConnections.set(clientIP, ipCount + 1);

// On close
const currentCount = ipConnections.get(clientIP) || 1;
if (currentCount <= 1) {
  ipConnections.delete(clientIP);
} else {
  ipConnections.set(clientIP, currentCount - 1);
}

Security Assessment: ✅ GOOD

• Prevents connection flooding from single IP
• Properly tracks connection/disconnection
• 5 connections is reasonable for multi-device scenarios

Potential Issue: ⚠️ Does not defend against distributed attacks (multiple IPs)

Recommendations:

• Add global connection limit (e.g., max 1000 total connections)
• Implement connection rate limiting (max N new connections per minute per IP)

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8. Origin Validation

Implementation: Lines 27-37, 255-263, 301-306

const ALLOWED_ORIGINS = new Set([
  'http://localhost:3000',
  'https://edge-net.ruv.io',
  // ... other allowed origins
]);

function isOriginAllowed(origin) {
  if (!origin) return true; // Allow Node.js connections
  if (ALLOWED_ORIGINS.has(origin)) return true;
  if (origin.startsWith('http://localhost:')) return true; // Dev mode
  return false;
}

if (!isOriginAllowed(origin)) {
  ws.close(4001, 'Unauthorized origin');
  return;
}

Security Assessment: ✅ GOOD for browser connections

Recommendations:

• ⚠️ if (!origin) return true allows any non-browser client (CLI, scripts)
• Consider requiring API key or authentication for non-browser connections:

function isOriginAllowed(origin, headers) {
  if (!origin) {
    // Non-browser connection - require API key
    const apiKey = headers['x-api-key'];
    return apiKey && validateAPIKey(apiKey);
  }
  return ALLOWED_ORIGINS.has(origin) || origin.startsWith('http://localhost:');
}

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9. Task Expiration

Implementation: Lines 243-253

// Cleanup old assigned tasks (expire after 5 minutes)
setInterval(() => {
  const now = Date.now();
  const TASK_TIMEOUT = 5 * 60 * 1000; // 5 minutes
  for (const [taskId, task] of assignedTasks) {
    if (now - task.assignedAt > TASK_TIMEOUT) {
      assignedTasks.delete(taskId);
      console.log(`Task ${taskId} expired (not completed in time)`);
    }
  }
}, 60000); // Check every minute

Security Assessment: ✅ GOOD

• Prevents stale task assignments
• 5-minute timeout is reasonable
• Automatically cleans up abandoned tasks

Recommendation: ⚠️ Consider re-queuing expired tasks:

if (now - task.assignedAt > TASK_TIMEOUT) {
  assignedTasks.delete(taskId);

  // Re-queue task if original submitter still connected
  if (nodes.has(task.submitter)) {
    taskQueue.push({
      id: taskId,
      submitter: task.submitter,
      // ... task details
    });
    console.log(`Task ${taskId} re-queued after timeout`);
  }
}

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10. Heartbeat Timeout

Implementation: Lines 25, 320-329

const CONNECTION_TIMEOUT = 30000; // 30s heartbeat timeout

let heartbeatTimeout;
const resetHeartbeat = () => {
  clearTimeout(heartbeatTimeout);
  heartbeatTimeout = setTimeout(() => {
    console.log(`Node ${nodeId} timed out`);
    ws.terminate();
  }, CONNECTION_TIMEOUT);
};
resetHeartbeat();

// Reset on any message
ws.on('message', async (data) => {
  resetHeartbeat();
  // ...
});

Security Assessment: ✅ GOOD

• Prevents zombie connections
• 30-second timeout with implicit heartbeat (any message resets)
• Explicit heartbeat message type also supported (lines 651-657)

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Remaining Vulnerabilities

🔴 CRITICAL (Production Blockers)

1. No Cryptographic Signature Verification
   • Impact: Cannot prove public key ownership
   • Mitigation: Implement Ed25519 signature validation (see recommendations above)
   • Priority: CRITICAL for production

🟡 MEDIUM (Should Address)

2. Unbounded completedTasks Set Growth

   • Impact: Memory leak over time
   • Mitigation: Implement periodic cleanup of old completed tasks
   • Priority: MEDIUM

3. No Global Connection Limit

   • Impact: Distributed attack from many IPs could exhaust resources
   • Mitigation: Add global max connection limit
   • Priority: MEDIUM

4. Permissive Non-Browser Access

   • Impact: Any script can connect without authentication
   • Mitigation: Require API key for non-browser connections
   • Priority: MEDIUM (depends on use case)

🟢 LOW (Nice to Have)

5. Error Messages Reveal Internal State

   • Impact: Attackers can infer system behavior from detailed errors
   • Mitigation: Use generic error messages in production, detailed in logs
   • Priority: LOW

6. No Firestore Access Control Validation

   • Impact: Assumes Firestore security rules are correctly configured
   • Mitigation: Document required Firestore security rules
   • Priority: LOW (infrastructure concern)

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Firestore Security Rules Required

The relay assumes these Firestore security rules are in place:

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /edge-net-qdag/{publicKey} {
      // Only server (via Admin SDK) can write
      allow read: if false;  // Not public
      allow write: if false; // Server-only
    }
  }
}

Validation: ⚠️ Not tested in this audit - infrastructure team should verify.

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Test Coverage Summary

Created comprehensive security test suite: /tests/relay-security.test.ts

Test Suites:

1. ✅ Task Completion Spoofing (2 tests)
2. ✅ Replay Attacks (1 test)
3. ✅ Credit Self-Reporting (2 tests)
4. ✅ Public Key Spoofing (2 tests)
5. ✅ Rate Limiting (1 test)
6. ✅ Message Size Limits (1 test)
7. ✅ Connection Limits (1 test)
8. ✅ Task Expiration (1 test)
9. ✅ Combined Attack Scenario (1 test)

Total: 12 security tests

To Run Tests:

cd /workspaces/ruvector/examples/edge-net
npm install --save-dev @jest/globals ws @types/ws
npm test tests/relay-security.test.ts

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Recommendations Summary

Immediate (Before Production)

1. ✅ Implement Ed25519 signature verification for public key ownership
2. ✅ Add challenge-response on node registration
3. ✅ Implement completedTasks cleanup to prevent memory leak

Short-term (1-2 weeks)

4. ✅ Add global connection limit (e.g., 1000 max total)
5. ✅ Require API keys for non-browser connections
6. ✅ Add separate rate limits for expensive operations
7. ✅ Rate-limit balance queries to prevent enumeration

Long-term (1-3 months)

8. ✅ Implement reputation-based rate limiting
9. ✅ Add connection rate limiting (per IP)
10. ✅ Use generic error messages in production
11. ✅ Document Firestore security rules and validate configuration
12. ✅ Add metrics and monitoring for attack detection

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Conclusion

The Edge-Net relay server demonstrates strong security fundamentals with excellent protection against:

• ✅ Task completion spoofing
• ✅ Replay attacks
• ✅ Credit self-reporting
• ✅ Basic DoS attacks

The QDAG ledger architecture is well-designed with Firestore as source of truth and server-side-only crediting.

Primary concern: Lack of cryptographic signature verification means public key ownership is not proven. This is acceptable for testing/development but MUST be implemented before production deployment.

Overall Assessment: System is secure for testing/development. Implement critical recommendations before production.

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Audit Completed: 2026-01-03 Next Review: After signature verification implementation