> For the complete documentation index, see [llms.txt](https://sspwallet.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sspwallet.gitbook.io/docs/security-and-best-practices/security-overview.md).

# Security Overview

## SSP's Security-First Approach

SSP Wallet is designed with **security as the foundation**, not an afterthought. Every component, communication, and operation is built to protect your cryptocurrency assets using industry-leading security practices.

## 🛡️ Core Security Principles

### 1. **True 2-of-2 Multisignature**

* **Both keys required** for every transaction
* **No single point of failure** in the system
* **Cryptographically enforced** security at the blockchain level

### 2. **Zero-Knowledge Architecture**

* Private keys **never leave your devices**
* SSP Relay **cannot access** sensitive data
* **TLS-encrypted in transit**; the relay is **zero-knowledge**, handling only **public data** (xpubs, identities, public nonces, scripts, addresses) — never seeds, keys, or signatures

### 3. **Self-Custody First**

* **You control** all private keys
* **No third-party custody** of funds
* **Full ownership** of your cryptocurrency

### 4. **Defense in Depth**

* **Multiple security layers** working together
* **Redundant protection** mechanisms
* **Graceful failure modes** that prioritize security

## 🔒 Security Layers

### Layer 1: Runtime Security

```
┌─────────────────────────────────────────┐
│          Runtime Security              │
├─────────────────────────────────────────┤
│ • LavaMoat Compartmentalization        │
│ • SES Lockdown Protection              │
│ • Supply Chain Attack Prevention       │
│ • Module Isolation (70+ packages)      │
│ • User-Verifiable Security Tests       │
└─────────────────────────────────────────┘
```

> **Try it yourself!** Click the version number in the wallet footer 5 times rapidly to access the built-in security test page and verify all protections are active.

### Layer 2: Device Security

```
┌─────────────────────────────────────────┐
│           Device Security               │
├─────────────────────────────────────────┤
│ • Password/PIN Protection               │
│ • Device Fingerprinting                 │
│ • Secure Storage (Keychain/MMKV)       │
│ • Biometric Authentication (Optional)   │
└─────────────────────────────────────────┘
```

### Layer 3: Cryptographic Security

```
┌─────────────────────────────────────────┐
│        Cryptographic Security          │
├─────────────────────────────────────────┤
│ • AES-256-GCM Encryption               │
│ • PBKDF2 Key Derivation                │
│ • Schnorr/ECDSA Signatures             │
│ • BIP48 HD Wallet Standard             │
└─────────────────────────────────────────┘
```

### Layer 4: Communication Security

```
┌─────────────────────────────────────────┐
│       Communication Security           │
├─────────────────────────────────────────┤
│ • TLS 1.3 Encryption                   │
│ • Message Authentication Codes         │
│ • Replay Attack Protection             │
│ • Zero-Knowledge Relay (public data)   │
└─────────────────────────────────────────┘
```

### Layer 5: Network Security

```
┌─────────────────────────────────────────┐
│          Network Security              │
├─────────────────────────────────────────┤
│ • Secure Blockchain RPC Endpoints      │
│ • Transaction Verification             │
│ • Double-Spend Protection              │
│ • Network Fee Validation               │
└─────────────────────────────────────────┘
```

## 🔐 Encryption Implementation

### Private Key Encryption

```javascript
// Simplified encryption flow
const encryptPrivateKey = (privateKey, password, deviceFingerprint) => {
  // 1. Generate random salt and IV
  const salt = crypto.getRandomValues(new Uint8Array(32));
  const iv = crypto.getRandomValues(new Uint8Array(16));
  
  // 2. Derive encryption key using PBKDF2
  const derivedKey = PBKDF2(password + deviceFingerprint, salt, 100000);
  
  // 3. Encrypt using AES-256-GCM
  const encrypted = AES_GCM.encrypt(privateKey, derivedKey, iv);
  
  return {
    data: base64(encrypted),
    salt: base64(salt),
    iv: base64(iv)
  };
};
```

### Key Derivation (BIP48)

```
Master Seed
    ↓
m/48'/cointype'/account'/script_type'/change/index
    ↓
Example Bitcoin: m/48'/0'/0'/2'/0/0
Example Ethereum: m/48'/60'/0'/0'/0/0
```

## 🛡️ Attack Resistance

### Protected Against

✅ **Single Device Compromise**: 2-of-2 multisig protects your funds ✅ **Phishing Attacks**: Address validation and device verification ✅ **Man-in-the-Middle**: Browser/OS-enforced TLS plus a zero-knowledge relay that only handles public data, so a MITM cannot recover keys or secrets ✅ **Brute Force**: Strong encryption and device fingerprinting ✅ **Server Compromise**: Zero-knowledge architecture protects keys ✅ **Replay Attacks**: Nonce-based message authentication ✅ **Social Engineering**: Multi-device approval required ✅ **Supply Chain Attacks**: LavaMoat compartmentalization and policies ✅ **Code Injection**: SES lockdown blocks eval and dynamic code execution ✅ **Prototype Pollution**: Immutable prototypes prevent tampering

### Potential Risks (Mitigated)

⚠️ **Both Device Loss**: Mitigated by seed phrase backup ⚠️ **User Error**: Mitigated by clear UI and confirmation steps ⚠️ **Physical Attack**: Mitigated by password protection ⚠️ **Compromised Dependencies**: Mitigated by LavaMoat runtime protection

## 🔍 Security Audits

### Professional Security Audits

SSP has undergone comprehensive security audits by [**Halborn Security**](https://halborn.com/):

#### 📄 **SSP Wallet, Key, and Relay Audit (2025)**

* **Scope**: Browser extension, mobile apps, and relay server
* **Focus**: Cross-device security, encryption, and communication protocols
* **Result**: Comprehensive security validation completed
* [**View Public Report**](https://www.halborn.com/audits/influx-technologies/ssp-wallet-relay-and-key)

#### 📄 **Smart Contracts Audit (2025)**

* **Scope**: Account Abstraction smart contracts with Schnorr multisig
* **Focus**: ERC-4337 implementation and cryptographic security
* **Result**: Smart contract security validated
* [**View Public Report**](https://www.halborn.com/audits/influx-technologies/account-abstraction-schnorr-multisig)

#### 📄 **SDK Security Audit (2025)**

* **Scope**: Account Abstraction SDK with Schnorr signatures
* **Focus**: Developer integration security and cryptographic implementation
* **Result**: SDK security practices validated
* [**View Public Report**](https://www.halborn.com/audits/influx-technologies/account-abstraction-schnorr-signatures-sdk)

## 🚨 Security Best Practices for Users

### Essential Practices

1. **📱 Keep Both Devices Secure**
   * Use strong passwords/PINs
   * Enable biometric authentication when available
   * Keep software updated
2. **🔄 Backup Your Seed Phrases**
   * Store both wallet and key seed phrases separately
   * Use secure, offline storage methods
   * Test recovery procedures
3. **🔍 Verify Transactions**
   * Always verify recipient addresses
   * Check transaction amounts carefully
   * Confirm network fees are reasonable
4. **🛡️ Stay Alert**
   * Be suspicious of unsolicited communications
   * Verify website URLs carefully
   * Never share seed phrases or private keys

### Advanced Security

1. **🔐 Multi-Location Backup**
   * Store seed phrases in different physical locations
   * Consider safety deposit boxes for large holdings
   * Use fire-proof and water-proof storage
2. **📊 Regular Wallet Review**
   * Review transaction history regularly
   * Verify both devices sync properly
   * Keep backup seed phrases secure and accessible

## 🆘 Security Incident Response

### If You Suspect Compromise

1. **🚨 Immediate Actions**
   * Stop all transactions immediately
   * Disconnect from networks if possible
   * Document any suspicious activity
2. **🔍 Assessment**
   * Check transaction history for unauthorized activity
   * Verify both devices are still secure
   * Review recent account access
3. **🔄 Recovery**
   * A single compromised device cannot move funds on its own — every transaction still requires both keys. While you still control both keys, use **both** devices together to move funds to a newly created wallet, then stop using the old setup
   * Create new wallet with fresh seed phrases
   * Report incident to security team

### Report Security Issues

* **GitHub Security**: [Report security vulnerabilities](https://github.com/RunOnFlux/ssp-wallet/security)
* **GitHub Issues**: [General security questions](https://github.com/RunOnFlux/ssp-wallet/issues)
* **Responsible Disclosure**: Use GitHub's security reporting features

## 🔬 Technical Security Details

### Cryptographic Specifications

* **Encryption**: AES-256-GCM with random IVs
* **Key Derivation**: PBKDF2 with 100,000+ iterations
* **Signatures**: ECDSA (Bitcoin and other UTXO chains), Schnorr multisig (EVM/Ethereum via ERC-4337 Account Abstraction), ed25519 (Solana)
* **Hashing**: SHA-256 for Bitcoin, Keccak-256 for Ethereum
* **HD Wallets**: BIP48 derivation for multisignature wallets

### Security Architecture

* **Open Source**: Transparent code for community security review
* **Deterministic Builds**: Verifiable build process with SHA256 checksums
* **Runtime Protection**: LavaMoat compartmentalization and SES lockdown
* **Regular Updates**: Continuous security improvements
* **Community Security**: GitHub-based security reporting

## 🏗️ Deterministic Builds

SSP Wallet implements **deterministic builds** to ensure complete transparency and verifiability of browser extension packages. This means anyone can rebuild the exact same packages and verify the integrity of what's submitted to browser stores.

### Why This Matters for Security

```
┌──────────────────────────────────────────┐
│    Deterministic Build Protection        │
├──────────────────────────────────────────┤
│ ✅ Verifiable Integrity                  │
│ ✅ No Hidden Code Injection              │
│ ✅ Reproducible Across Machines          │
│ ✅ Browser Store Verification            │
│ ✅ Build-Time Supply Chain Protection    │
└──────────────────────────────────────────┘
```

The same source code **always** produces byte-identical binaries, making it impossible to inject malicious code during the build process without detection.

### Quick Verification

```bash
# Clone the repository
git clone https://github.com/RunOnFlux/ssp-wallet.git
cd ssp-wallet

# Build using Docker for reproducibility
npm run build:deterministic

# Verify SHA256 hashes match published version
sha256sum -c SHA256SUMS
```

### Build Environment

* **Docker Image**: `node:24.11.1-alpine` (SHA-pinned)
* **Fixed Timestamp**: 2025-01-01 00:00:00 UTC (eliminates variation)
* **Frozen Dependencies**: `yarn.lock` ensures exact versions
* **Isolated Environment**: No host dependencies affect output
* **Output**: SHA256-verified Chrome and Firefox packages

### Security Guarantees

**Protected Against:**

* ❌ Build environment attacks (Docker isolation)
* ❌ Supply chain substitution (frozen dependencies)
* ❌ Timestamp manipulation (fixed SOURCE\_DATE\_EPOCH)
* ❌ Hidden build steps (complete reproducibility)

**Verified By:**

* ✅ Security auditors can rebuild and verify
* ✅ Browser store reviewers can validate submissions
* ✅ Community members can independently verify
* ✅ SHA256 checksums provide cryptographic proof

For complete technical details, build instructions, troubleshooting, and Docker configuration, see the [**Deterministic Builds Developer Guide**](/docs/ssp-wallet-development/deterministic-builds.md).

## Next Steps

* [**Runtime Security with LavaMoat**](/docs/security-and-best-practices/runtime-security.md) - Deep dive into runtime protection and supply chain security
* [**Deterministic Builds Guide**](/docs/ssp-wallet-development/deterministic-builds.md) - Complete guide to verifying and reproducing builds
* [**Halborn Security Audit**](/docs/security-and-best-practices/halborn-audit-2025.md) - Complete audit results and findings
* [**Device Security Guidelines**](/docs/security-and-best-practices/device-security.md) - Secure your SSP Wallet devices
* [**GitHub Security**](https://github.com/RunOnFlux/ssp-wallet/security) - Report security issues
* [**Interactive Setup Tutorial**](https://sspwallet.io/guide) - Secure wallet setup guide