# @ruvector/edge-net Security Review

## Executive Summary

This document provides a comprehensive security analysis of the edge-net distributed compute network. The system enables browsers to contribute compute power and earn credits, creating a P2P marketplace for AI workloads.

**Security Classification: HIGH RISK**

A distributed compute network with financial incentives presents significant attack surface. This review identifies threats, mitigations, and remaining risks.

---

## Table of Contents

1. [Threat Model](#1-threat-model)
2. [Attack Vectors](#2-attack-vectors)
3. [Security Controls](#3-security-controls)
4. [QDAG Currency Security](#4-qdag-currency-security)
5. [Cryptographic Choices](#5-cryptographic-choices)
6. [Remaining Risks](#6-remaining-risks)
7. [Security Recommendations](#7-security-recommendations)
8. [Incident Response](#8-incident-response)

---

## 1. Threat Model

### 1.1 Assets at Risk

| Asset | Value | Impact if Compromised |
|-------|-------|----------------------|
| **User credits** | Financial | Direct monetary loss |
| **Task payloads** | Confidential | Data breach, IP theft |
| **Compute results** | Integrity | Incorrect AI outputs |
| **Node identities** | Reputation | Impersonation, fraud |
| **Network state** | Availability | Service disruption |
| **QDAG ledger** | Financial | Double-spend, inflation |

### 1.2 Threat Actors

| Actor | Capability | Motivation |
|-------|------------|------------|
| **Script kiddie** | Low | Vandalism, testing |
| **Fraudster** | Medium | Credit theft, fake compute |
| **Competitor** | Medium-High | Disruption, espionage |
| **Nation-state** | Very High | Surveillance, sabotage |
| **Insider** | High | Financial gain |

### 1.3 Trust Boundaries

```
┌─────────────────────────────────────────────────────────────────────────┐
│                        UNTRUSTED ZONE                                   │
│                                                                         │
│   ┌─────────────┐        ┌─────────────┐        ┌─────────────┐        │
│   │  Malicious  │        │   Network   │        │   Rogue     │        │
│   │   Client    │        │   Traffic   │        │   Worker    │        │
│   └──────┬──────┘        └──────┬──────┘        └──────┬──────┘        │
│          │                      │                      │                │
├──────────┼──────────────────────┼──────────────────────┼────────────────┤
│          │            TRUST BOUNDARY                   │                │
├──────────┼──────────────────────┼──────────────────────┼────────────────┤
│          ▼                      ▼                      ▼                │
│   ┌─────────────────────────────────────────────────────────────┐      │
│   │                    EDGE-NET NODE                             │      │
│   │                                                              │      │
│   │  ┌──────────┐   ┌──────────┐   ┌──────────┐   ┌──────────┐  │      │
│   │  │ Identity │   │  QDAG    │   │   Task   │   │ Security │  │      │
│   │  │ Verify   │   │  Verify  │   │  Verify  │   │  Checks  │  │      │
│   │  └──────────┘   └──────────┘   └──────────┘   └──────────┘  │      │
│   │                                                              │      │
│   │  ┌──────────────────────────────────────────────────────┐   │      │
│   │  │              WASM SANDBOX (Trusted)                   │   │      │
│   │  │  ┌────────────┐  ┌────────────┐  ┌────────────┐      │   │      │
│   │  │  │  Compute   │  │   Credit   │  │   Crypto   │      │   │      │
│   │  │  │  Execution │  │   Ledger   │  │   Engine   │      │   │      │
│   │  │  └────────────┘  └────────────┘  └────────────┘      │   │      │
│   │  └──────────────────────────────────────────────────────┘   │      │
│   │                                                              │      │
│   └─────────────────────────────────────────────────────────────┘      │
│                                                                         │
│                         TRUSTED ZONE                                    │
└─────────────────────────────────────────────────────────────────────────┘
```

---

## 2. Attack Vectors

### 2.1 Sybil Attacks

**Threat:** Attacker creates many fake identities to:
- Claim disproportionate compute rewards
- Manipulate task verification voting
- Control consensus outcomes

**Mitigations Implemented:**
```rust
// Browser fingerprinting (privacy-preserving)
BrowserFingerprint::generate() -> unique hash

// Stake requirement
const MIN_STAKE: u64 = 100_000_000; // 100 credits to participate

// Rate limiting
RateLimiter::check_allowed(node_id) -> bool

// Sybil defense
SybilDefense::register_node(node_id, fingerprint) -> bool (max 3 per fingerprint)
```

**Residual Risk:** MEDIUM
- Fingerprinting can be bypassed with VMs/incognito
- Stake requirement helps but motivated attackers can acquire credits
- Recommendation: Add proof-of-humanity (optional) for high-value operations

### 2.2 Free-Riding Attacks

**Threat:** Attacker claims compute rewards without doing real work:
- Returns random/garbage results
- Copies results from honest workers
- Times out intentionally

**Mitigations Implemented:**
```rust
// Redundant execution (N workers verify same task)
task.redundancy = 3; // 3 workers, majority wins

// Spot-checking with known answers
SpotChecker::should_check() -> 10% of tasks verified
SpotChecker::verify_response(input, output) -> bool

// Execution proofs
ExecutionProof {
    io_hash: hash(input + output),
    checkpoints: Vec<intermediate_hashes>,
}

// Reputation consequences
ReputationSystem::record_penalty(node_id, 0.3); // 30% reputation hit
```

**Residual Risk:** LOW-MEDIUM
- Redundancy provides strong protection but costs 3x compute
- Spot-checks effective but can be gamed if challenges leak
- Recommendation: Implement rotating challenge set, consider ZK proofs

### 2.3 Double-Spend Attacks (QDAG)

**Threat:** Attacker spends same credits twice:
- Creates conflicting transactions
- Exploits network partitions
- Manipulates cumulative weight

**Mitigations Implemented:**
```rust
// DAG structure prevents linear double-spend
tx.validates = vec![parent1, parent2]; // Must reference 2+ existing tx

// Cumulative weight (similar to confirmation depth)
cumulative_weight = sum(parent_weights) + 1;

// Proof of work (spam prevention)
pow_difficulty = 16; // ~65K hashes per tx

// Cryptographic signatures
tx.signature_ed25519 = sign(hash(tx_content));
```

**Residual Risk:** MEDIUM
- DAG is more complex than blockchain, edge cases possible
- No formal verification of consensus properties
- Recommendation: Model with TLA+ or similar, add watchtower nodes

### 2.4 Task Injection Attacks

**Threat:** Attacker submits malicious tasks:
- Exfiltrate worker data
- Execute arbitrary code
- Denial of service via resource exhaustion

**Mitigations Implemented:**
```rust
// Task type whitelist
match task.task_type {
    TaskType::VectorSearch => ..., // Known, safe operations
    TaskType::CustomWasm => Err("Requires explicit verification"),
}

// Resource limits
WasmTaskExecutor {
    max_memory: 256 * 1024 * 1024, // 256MB
    max_time_ms: 30_000,           // 30 seconds
}

// Payload encryption (only intended recipient can read)
encrypted_payload = encrypt(payload, recipient_pubkey);

// Signature verification
verify_signature(task, submitter_pubkey);
```

**Residual Risk:** LOW
- WASM sandbox provides strong isolation
- Resource limits prevent DoS
- CustomWasm explicitly disabled by default
- Recommendation: Add task size limits, implement quota system

### 2.5 Man-in-the-Middle Attacks

**Threat:** Attacker intercepts and modifies network traffic:
- Steal task payloads
- Modify results
- Impersonate nodes

**Mitigations Implemented:**
```rust
// End-to-end encryption
task.encrypted_payload = aes_gcm_encrypt(key, payload);

// Message authentication
signature = ed25519_sign(private_key, message);

// Node identity verification
verify(public_key, message, signature);
```

**Residual Risk:** LOW
- E2E encryption prevents content inspection
- Signatures prevent modification
- Recommendation: Implement certificate pinning for relay connections

### 2.6 Denial of Service

**Threat:** Attacker overwhelms network:
- Flood with fake tasks
- Exhaust relay resources
- Target specific nodes

**Mitigations Implemented:**
```rust
// Rate limiting
RateLimiter {
    window_ms: 60_000,  // 1 minute window
    max_requests: 100,  // 100 requests max
}

// Stake requirement (economic cost to attack)
min_stake: 100_000_000

// PoW for QDAG transactions
pow_difficulty: 16 // Computational cost per tx

// Task expiration
expires_at: now + 60_000 // Tasks expire in 1 minute
```

**Residual Risk:** MEDIUM
- Distributed nature helps absorb attacks
- Relays are still centralized chokepoints
- Recommendation: Deploy multiple relay providers, implement circuit breakers

---

## 3. Security Controls

### 3.1 Control Matrix

| Control | Type | Status | Effectiveness |
|---------|------|--------|---------------|
| Ed25519 signatures | Cryptographic | Implemented | High |
| AES-256-GCM encryption | Cryptographic | Implemented | High |
| WASM sandboxing | Isolation | Implemented | High |
| Rate limiting | Availability | Implemented | Medium |
| Stake requirement | Economic | Implemented | Medium |
| Reputation system | Behavioral | Implemented | Medium |
| Sybil defense | Identity | Implemented | Low-Medium |
| Spot-checking | Verification | Implemented | Medium |
| Audit logging | Detection | Implemented | Medium |

### 3.2 Defense in Depth

```
┌─────────────────────────────────────────────────────────────────────────┐
│ Layer 1: Network (Rate limiting, PoW, Geographic diversity)            │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 2: Identity (Ed25519, Fingerprinting, Reputation)                │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 3: Economic (Stake, Credits, Penalties)                          │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 4: Cryptographic (AES-GCM, Signatures, Hashing)                  │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 5: Isolation (WASM sandbox, Resource limits)                     │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 6: Verification (Redundancy, Spot-checks, Proofs)                │
├─────────────────────────────────────────────────────────────────────────┤
│ Layer 7: Detection (Audit logs, Anomaly detection)                     │
└─────────────────────────────────────────────────────────────────────────┘
```

---

## 4. QDAG Currency Security

### 4.1 Consensus Properties

| Property | Status | Notes |
|----------|--------|-------|
| **Safety** | Partial | DAG prevents simple double-spend, but lacks formal proof |
| **Liveness** | Yes | Feeless, always possible to transact |
| **Finality** | Probabilistic | Higher weight = more confirmations |
| **Censorship resistance** | Yes | No miners/validators to bribe |

### 4.2 Attack Resistance

| Attack | Resistance | Mechanism |
|--------|------------|-----------|
| Double-spend | Medium | Cumulative weight, redundancy |
| 51% attack | N/A | No mining, all nodes equal |
| Sybil | Medium | Stake + fingerprinting |
| Spam | Medium | PoW + rate limiting |
| Front-running | Low | Transactions are public |

### 4.3 Economic Security

```
Attack Cost Analysis:

Scenario: Attacker wants to double-spend 1000 credits

1. Stake requirement: 100 credits minimum
2. PoW cost: ~65K hashes × transaction fee (0) = ~$0.01 electricity
3. Detection probability: ~90% (redundancy + spot-checks)
4. Penalty if caught: Stake slashed (100 credits) + reputation damage

Expected Value:
  Success (10%): +1000 credits
  Failure (90%): -100 credits (stake) - reputation

  EV = 0.1 × 1000 - 0.9 × 100 = 100 - 90 = +10 credits

PROBLEM: Positive expected value for attack!

Mitigation needed:
- Increase stake requirement to 200+ credits
- Add delayed finality (1 hour) for large transfers
- Require higher redundancy for high-value tasks
```

### 4.4 Recommended Improvements

1. **Increase minimum stake to 1000 credits** for contributor nodes
2. **Implement time-locked withdrawals** (24h delay for large amounts)
3. **Add transaction confirmation threshold** (weight > 10 for finality)
4. **Watchdog nodes** that monitor for conflicts and alert

---

## 5. Cryptographic Choices

### 5.1 Algorithm Selection

| Use Case | Algorithm | Key Size | Security Level | Quantum Safe |
|----------|-----------|----------|----------------|--------------|
| Signatures | Ed25519 | 256-bit | 128-bit | No |
| Encryption | AES-256-GCM | 256-bit | 256-bit | Partial |
| Hashing | SHA-256 | 256-bit | 128-bit | Partial |
| Key exchange | X25519 | 256-bit | 128-bit | No |

### 5.2 Quantum Resistance Roadmap

Current implementation is NOT quantum-safe. Mitigation plan:

**Phase 1 (Current):** Ed25519 + AES-256-GCM
- Sufficient for near-term (5-10 years)
- Fast and well-tested

**Phase 2 (Planned):** Hybrid signatures
```rust
pub struct HybridSignature {
    ed25519: [u8; 64],
    dilithium: Option<[u8; 2420]>,  // Post-quantum
}
```

**Phase 3 (Future):** Full post-quantum
- Replace X25519 with CRYSTALS-Kyber
- Replace Ed25519 with CRYSTALS-Dilithium
- Timeline: When NIST standards are finalized and WASM support available

### 5.3 Key Management

| Key Type | Storage | Lifecycle | Rotation |
|----------|---------|-----------|----------|
| Identity private key | localStorage (encrypted) | Long-term | On compromise only |
| Task encryption key | Memory only | Per-task | Every task |
| Session key | Memory only | Per-session | Every session |

**Recommendations:**
1. Add option to export/backup identity keys
2. Implement key derivation for sub-keys
3. Consider hardware security module integration

---

## 6. Remaining Risks

### 6.1 High Priority

| Risk | Likelihood | Impact | Mitigation Status |
|------|------------|--------|-------------------|
| QDAG double-spend | Medium | High | Partial - needs more stake |
| Relay compromise | Medium | High | Not addressed - single point of failure |
| Fingerprint bypass | High | Medium | Accepted - layered defense |

### 6.2 Medium Priority

| Risk | Likelihood | Impact | Mitigation Status |
|------|------------|--------|-------------------|
| Quantum computer attack | Low (5+ years) | Critical | Planned - hybrid signatures |
| Result manipulation | Medium | Medium | Implemented - redundancy |
| Credit inflation | Low | High | Implemented - max supply cap |

### 6.3 Accepted Risks

| Risk | Rationale for Acceptance |
|------|--------------------------|
| Browser fingerprint bypass | Defense in depth, not sole protection |
| Front-running | Low value per transaction |
| Denial of service on single node | Network is distributed |

---

## 7. Security Recommendations

### 7.1 Immediate (Before Launch)

1. **Increase minimum stake to 1000 credits**
   - Current 100 credits allows profitable attacks
   - Higher stake increases attacker cost

2. **Add time-locked withdrawals for large amounts**
   ```rust
   if amount > 10_000 {
       withdrawal_delay = 24 * 60 * 60 * 1000; // 24 hours
   }
   ```

3. **Implement relay redundancy**
   - Use 3+ relay providers
   - Implement failover logic
   - Monitor relay health

4. **Add anomaly detection**
   - Monitor for unusual transaction patterns
   - Alert on reputation drops
   - Track geographic distribution

### 7.2 Short-Term (1-3 Months)

1. **Formal verification of QDAG consensus**
   - Model in TLA+ or similar
   - Prove safety properties
   - Test with chaos engineering

2. **Bug bounty program**
   - Engage external security researchers
   - Reward vulnerability disclosure
   - Range: $500 - $50,000 based on severity

3. **Penetration testing**
   - Engage professional red team
   - Focus on economic attacks
   - Test at scale

### 7.3 Long-Term (3-12 Months)

1. **Post-quantum cryptography migration**
   - Implement Dilithium signatures
   - Implement Kyber key exchange
   - Maintain backward compatibility

2. **Hardware security module support**
   - WebAuthn integration for identity
   - Secure key storage
   - Biometric authentication

3. **Decentralized relay network**
   - Run relay nodes on-chain
   - Incentivize relay operators
   - Eliminate single points of failure

---

## 8. Incident Response

### 8.1 Incident Categories

| Category | Examples | Response Time |
|----------|----------|---------------|
| P1 - Critical | Double-spend, key compromise | < 1 hour |
| P2 - High | Relay outage, spam attack | < 4 hours |
| P3 - Medium | Reputation manipulation, minor bugs | < 24 hours |
| P4 - Low | Performance issues, UI bugs | < 1 week |

### 8.2 Response Procedures

**P1 - Critical Incident:**
1. Pause network (if possible)
2. Assess damage scope
3. Identify root cause
4. Deploy fix
5. Restore service
6. Post-mortem

**Contacts:**
- Security lead: security@ruvector.dev
- Emergency: See internal runbook
- Bug bounty: hackerone.com/ruvector (pending)

### 8.3 Disclosure Policy

- **Private disclosure preferred** for critical vulnerabilities
- **90-day disclosure window** before public release
- **Credit and bounty** for responsible disclosure
- **CVE assignment** for significant vulnerabilities

---

## Appendix A: Security Checklist

### Pre-Launch

- [ ] Minimum stake increased to 1000 credits
- [ ] Time-locked withdrawals implemented
- [ ] Multi-relay support tested
- [ ] Rate limits tuned for production
- [ ] Audit logs reviewed for gaps
- [ ] Key backup/recovery tested
- [ ] Incident response tested

### Post-Launch

- [ ] Bug bounty active
- [ ] Penetration test completed
- [ ] Formal verification started
- [ ] Monitoring dashboards live
- [ ] On-call rotation established

---

## Appendix B: References

1. NIST Post-Quantum Cryptography: https://csrc.nist.gov/Projects/post-quantum-cryptography
2. Ed25519 specification: https://ed25519.cr.yp.to/
3. AES-GCM: NIST SP 800-38D
4. DAG-based consensus: IOTA Tangle, Avalanche
5. Sybil attack mitigation: https://dl.acm.org/doi/10.1145/586110.586124

---

*This document should be reviewed quarterly and updated after any security incident.*

*Last reviewed: [DATE]*
*Next review: [DATE + 90 days]*