fix: HIGH+MEDIUM bugs from full audit - listen error, JWT, upload, mailer, webhook

backend/middleware/auth.js

@@ -4,8 +4,13 @@ const { getConfig } = require('../db');
 function getSecret() {
   try {
     const cfg = getConfig();
-    return cfg?.jwt_secret || process.env.JWT_SECRET || 'mc-dev-secret';
-  } catch { return process.env.JWT_SECRET || 'mc-dev-secret'; }
+    const secret = cfg?.jwt_secret || process.env.JWT_SECRET;
+    if (secret) return secret;
+    throw new Error('JWT_SECRET not configured');
+  } catch (e) {
+    if (e.message === 'JWT_SECRET not configured') throw e;
+    return process.env.JWT_SECRET || (() => { throw new Error('JWT_SECRET not configured'); })();
+  }
 }
 
 function generateToken(user) {

backend/middleware/security.js

@@ -33,13 +33,14 @@ function sanitize(value) {
 }
 
 function sanitizeBody(req, res, next) {
-  if (req.body) {
-    for (const key of Object.keys(req.body)) {
-      if (typeof req.body[key] === 'string') {
-        req.body[key] = sanitize(req.body[key]);
-      }
+  function walk(obj) {
+    if (!obj || typeof obj !== 'object') return;
+    for (const key of Object.keys(obj)) {
+      if (typeof obj[key] === 'string') obj[key] = sanitize(obj[key]);
+      else if (typeof obj[key] === 'object') walk(obj[key]);
     }
   }
+  walk(req.body);
   next();
 }
 

backend/middleware/upload.js

@@ -24,7 +24,7 @@ function validateMagicBytes(buffer, mime) {
     'image/png': () => head[0] === 0x89 && head[1] === 0x50 && head[2] === 0x4E && head[3] === 0x47,
     'image/gif': () => head.toString('ascii', 0, 6) === 'GIF89a' || head.toString('ascii', 0, 6) === 'GIF87a',
     'image/webp': () => head.toString('ascii', 0, 4) === 'RIFF' && head.toString('ascii', 8, 12) === 'WEBP',
-    'video/mp4': () => buffer.includes(Buffer.from('ftyp')),
+    'video/mp4': () => buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70,
     'video/webm': () => head[0] === 0x1A && head[1] === 0x45 && head[2] === 0xDF && head[3] === 0xA3,
   };
   if (!sigs[mime]) return false;
@@ -58,18 +58,22 @@ const upload = multer({
 
 function finalizeUpload(req, res, next) {
   if (!req.files || req.files.length === 0) return next();
-  for (const file of req.files) {
-    const buf = fs.readFileSync(file.path);
-    if (!ALLOWED_MIME[file.mimetype]) {
-      fs.unlinkSync(file.path);
-      return res.status(400).json({ error: `不支持的文件类型: ${file.mimetype}` });
-    }
-    if (!validateMagicBytes(buf, file.mimetype)) {
-      fs.unlinkSync(file.path);
-      return res.status(400).json({ error: '文件内容与声明类型不符，可能是恶意文件' });
+  const filePaths = [];
+  try {
+    for (const file of req.files) {
+      const fd = fs.openSync(file.path, 'r');
+      const buf = Buffer.alloc(256);
+      fs.readSync(fd, buf, 0, 256, 0);
+      fs.closeSync(fd);
+      filePaths.push(file.path);
+      if (!ALLOWED_MIME[file.mimetype]) throw new Error(`不支持的文件类型: ${file.mimetype}`);
+      if (!validateMagicBytes(buf, file.mimetype)) throw new Error('文件内容与声明类型不符，可能是恶意文件');
     }
+    next();
+  } catch (e) {
+    for (const fp of filePaths) { try { fs.unlinkSync(fp); } catch {} }
+    return res.status(400).json({ error: e.message || '文件校验失败' });
   }
-  next();
 }
 
 module.exports = { upload, finalizeUpload, validateMagicBytes, UPLOAD_DIR, ALLOWED_MIME };