feat(scanner): detect malicious WebSocket handlers

scanner/package.json

@@ -6,6 +6,7 @@
   "type": "module",
   "scripts": {
     "build": "tsc",
+    "test": "node --import tsx --test src/websocket-patterns.test.ts",
     "start": "node dist/index.js",
     "dev": "tsx watch src/index.ts",
     "scan": "tsx src/cli.ts"

scanner/src/patterns.ts

@@ -141,6 +141,30 @@ export const DANGEROUS_PATTERNS: Pattern[] = [
     pattern: /dns\.resolve|dns\.lookup.*[+`$]/gi,
     category: 'network'
   },
+  {
+    id: 'NET_WEBSOCKET_INSECURE',
+    name: 'Insecure or Suspicious WebSocket Endpoint',
+    description: 'WebSocket connection uses plaintext transport or a commonly abused tunnel endpoint',
+    severity: 'high',
+    pattern: /(?:new\s+)?WebSocket\s*\(\s*['"`](?:ws:\/\/|wss:\/\/[^'"`]*(?:ngrok(?:-free)?\.app|ngrok\.io|requestbin|pipedream|webhook\.site))/gi,
+    category: 'network'
+  },
+  {
+    id: 'EXFIL_WEBSOCKET_SEND',
+    name: 'Sensitive Data Sent over WebSocket',
+    description: 'WebSocket send includes credentials, environment variables, or file contents',
+    severity: 'critical',
+    pattern: /\.\s*send\s*\(\s*(?:JSON\.stringify\s*\([^)]*)?(?:process\.env|readFile(?:Sync)?\s*\(|credentials?|private[_-]?key|secret|token)/gi,
+    category: 'exfiltration'
+  },
+  {
+    id: 'EXEC_WEBSOCKET_MESSAGE',
+    name: 'Command Execution from WebSocket Message',
+    description: 'WebSocket message handler passes remote data to a command execution function',
+    severity: 'critical',
+    pattern: /\.on\s*\(\s*['"`]message['"`]\s*,[\s\S]{0,300}\b(?:exec|execSync|spawn|spawnSync)\s*\(/gi,
+    category: 'code_execution'
+  },
 
   // === MEDIUM: Obfuscation ===
   {

scanner/src/websocket-patterns.test.ts

@@ -0,0 +1,37 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { analyzeContent } from './analyzer.js';
+
+function findingIds(content: string): string[] {
+  return analyzeContent(content).findings.map(finding => finding.patternId);
+}
+
+test('detects plaintext WebSocket endpoints', () => {
+  assert.ok(findingIds("const socket = new WebSocket('ws://example.com/control')").includes('NET_WEBSOCKET_INSECURE'));
+});
+
+test('detects commonly abused WebSocket tunnel endpoints', () => {
+  assert.ok(findingIds("const socket = new WebSocket('wss://agent.ngrok-free.app/ws')").includes('NET_WEBSOCKET_INSECURE'));
+});
+
+test('allows ordinary secure WebSocket endpoints', () => {
+  assert.ok(!findingIds("const socket = new WebSocket('wss://example.com/events')").includes('NET_WEBSOCKET_INSECURE'));
+});
+
+test('detects environment variable exfiltration over WebSocket', () => {
+  assert.ok(findingIds('socket.send(process.env.API_TOKEN)').includes('EXFIL_WEBSOCKET_SEND'));
+});
+
+test('detects file content exfiltration over WebSocket', () => {
+  assert.ok(findingIds("socket.send(readFileSync('/tmp/data'))").includes('EXFIL_WEBSOCKET_SEND'));
+});
+
+test('detects command execution in a WebSocket message handler', () => {
+  const content = "socket.on('message', command => { exec(command) })";
+  assert.ok(findingIds(content).includes('EXEC_WEBSOCKET_MESSAGE'));
+});
+
+test('allows WebSocket message handlers without command execution', () => {
+  const content = "socket.on('message', message => { console.log(message) })";
+  assert.ok(!findingIds(content).includes('EXEC_WEBSOCKET_MESSAGE'));
+});