diff --git a/.gitignore b/.gitignore
index 0b651bca..2428ab44 100644
--- a/.gitignore
+++ b/.gitignore
@@ -35,3 +35,6 @@ __pycache__
 
 # local Kubernetes overlays
 /deploy/kubernetes/overlays/local/
+
+# Local security audit artifacts
+/audit/
diff --git a/back/api/config.ts b/back/api/config.ts
index 6eb4d997..c61772f5 100644
--- a/back/api/config.ts
+++ b/back/api/config.ts
@@ -9,6 +9,7 @@ import { SAMPLE_FILES } from '../config/const';
 import { t } from '../shared/i18n';
 import ConfigService from '../services/config';
 import { writeFileWithLock } from '../shared/utils';
+import { resolveFileAccess } from '../shared/fileAccess';
 const route = Router();
 
 export default (app: Router) => {
@@ -78,14 +79,12 @@ export default (app: Router) => {
           basePath = join(config.rootPath, 'data/scripts');
         }
         const cleanName = name.replace(/^data\/scripts\//, '');
-        const resolvedPath = join(basePath, cleanName);
-        const normalized = join(resolvedPath);
-        // Verify the resolved path stays within allowed directory
-        if (!normalized.startsWith(basePath)) {
-          return res.send({ code: 403, message: t('文件路径无效') });
-        }
-        // Check blacklist on actual filename (not user input)
-        if (config.blackFileList.includes(basename(normalized))) {
+        const normalized = resolveFileAccess(
+          basePath,
+          [cleanName],
+          config.blackFileList,
+        );
+        if (!normalized) {
           return res.send({ code: 403, message: t('文件无法访问') });
         }
         await writeFileWithLock(normalized, content);
@@ -96,13 +95,10 @@ export default (app: Router) => {
     },
   );
 
-  route.get(
-    '/:file',
-    (req: Request, res: Response) => {
-      return res.send({
-        code: 410,
-        message: t('接口已下线，请使用 /configs/detail 接口'),
-      });
-    },
-  );
+  route.get('/:file', (req: Request, res: Response) => {
+    return res.send({
+      code: 410,
+      message: t('接口已下线，请使用 /configs/detail 接口'),
+    });
+  });
 };
diff --git a/back/api/script.ts b/back/api/script.ts
index 11ba9137..99a63ad3 100644
--- a/back/api/script.ts
+++ b/back/api/script.ts
@@ -1,3 +1,5 @@
+import { randomUUID } from 'crypto';
+import { resolveFileAccess } from '../shared/fileAccess';
 import { fileExist, readDirs, readDir, rmPath, IFile } from '../config/util';
 import { Router, Request, Response, NextFunction } from 'express';
 import { Container } from 'typedi';
@@ -14,15 +16,17 @@ const route = Router();
 
 function isPathAllowed(targetPath: string): boolean {
   const resolved = path.resolve(targetPath);
-  return config.writePathList.some((x) => resolved.startsWith(x));
+  return config.writePathList.some((x) =>
+    Boolean(resolveFileAccess(x, [resolved], config.blackFileList)),
+  );
 }
 
 const storage = multer.diskStorage({
   destination: function (req, file, cb) {
-    cb(null, config.scriptPath);
+    cb(null, config.tmpPath);
   },
   filename: function (req, file, cb) {
-    cb(null, file.originalname);
+    cb(null, randomUUID());
   },
 });
 const upload = multer({ storage: storage });
@@ -50,6 +54,15 @@ export default (app: Router) => {
           'package-lock.json',
         ];
         if (req.query.path) {
+          if (
+            !resolveFileAccess(
+              config.scriptPath,
+              [req.query.path as string],
+              config.blackFileList,
+            )
+          ) {
+            return res.send({ code: 403, message: t('暂无权限') });
+          }
           result = await readDir(
             req.query.path as string,
             config.scriptPath,
@@ -77,7 +90,8 @@ export default (app: Router) => {
         logger.error('🔥 error: %o', e);
         return next(e);
       }
-    });
+    },
+  );
 
   route.get(
     '/detail',
@@ -91,7 +105,7 @@ export default (app: Router) => {
       try {
         const scriptService = Container.get(ScriptService);
         const content = await scriptService.getFile(
-          req.query?.path as string || '',
+          (req.query?.path as string) || '',
           req.query.file as string,
         );
         res.send({ code: 200, data: content });
@@ -101,18 +115,21 @@ export default (app: Router) => {
     },
   );
 
-  route.get(
-    '/:file',
-    (req: Request, res: Response) => {
-      return res.send({
-        code: 410,
-        message: t('接口已下线，请使用 /scripts/detail 接口'),
-      });
-    },
-  );
+  route.get('/:file', (req: Request, res: Response) => {
+    return res.send({
+      code: 410,
+      message: t('接口已下线，请使用 /scripts/detail 接口'),
+    });
+  });
 
   route.post(
     '/',
+    (req: Request, res: Response, next: NextFunction) => {
+      res.on('finish', () => {
+        if (req.file?.path) fs.unlink(req.file.path).catch(() => undefined);
+      });
+      next();
+    },
     upload.single('file'),
     celebrate({
       body: Joi.object({
@@ -156,7 +173,8 @@ export default (app: Router) => {
           if (!isPathAllowed(uploadPath)) {
             return res.send({ code: 403, message: t('暂无权限') });
           }
-          await fs.rename(req.file.path, uploadPath);
+          await fs.copyFile(req.file.path, uploadPath);
+          await fs.unlink(req.file.path);
           return res.send({ code: 200 });
         }
 
diff --git a/back/api/user.ts b/back/api/user.ts
index 4d526389..4e92b39b 100644
--- a/back/api/user.ts
+++ b/back/api/user.ts
@@ -22,7 +22,25 @@ const storage = multer.diskStorage({
     cb(null, key + ext);
   },
 });
-const upload = multer({ storage: storage });
+const upload = multer({
+  storage,
+  limits: { fileSize: 5 * 1024 * 1024, files: 1 },
+  fileFilter: (_req, file, cb) => {
+    const ext = path.extname(file.originalname).toLowerCase();
+    const imageTypes: Record<string, string> = {
+      '.png': 'image/png',
+      '.jpg': 'image/jpeg',
+      '.jpeg': 'image/jpeg',
+      '.gif': 'image/gif',
+      '.webp': 'image/webp',
+      '.avif': 'image/avif',
+    };
+    if (imageTypes[ext] !== file.mimetype) {
+      return cb(new Error(t('仅支持 PNG、JPEG、GIF、WebP、AVIF 图片')));
+    }
+    cb(null, true);
+  },
+});
 
 export default (app: Router) => {
   app.use('/user', route);
@@ -35,8 +53,8 @@ export default (app: Router) => {
     }),
     celebrate({
       body: Joi.object({
-        username: Joi.string().required(),
-        password: Joi.string().required(),
+        username: Joi.string().max(1024).required(),
+        password: Joi.string().max(1024).required(),
       }),
     }),
     async (req: Request, res: Response, next: NextFunction) => {
@@ -70,8 +88,8 @@ export default (app: Router) => {
     '/',
     celebrate({
       body: Joi.object({
-        username: Joi.string().required(),
-        password: Joi.string().required(),
+        username: Joi.string().max(1024).required(),
+        password: Joi.string().max(1024).required(),
       }),
     }),
     async (req: Request, res: Response, next: NextFunction) => {
@@ -156,11 +174,12 @@ export default (app: Router) => {
 
   route.put(
     '/two-factor/login',
+    rateLimit({ windowMs: 15 * 60 * 1000, max: 20 }),
     celebrate({
       body: Joi.object({
         code: Joi.string().required(),
-        username: Joi.string().required(),
-        password: Joi.string().required(),
+        username: Joi.string().max(1024).required(),
+        password: Joi.string().max(1024).required(),
       }),
     }),
     async (req: Request, res: Response, next: NextFunction) => {
@@ -272,17 +291,18 @@ export default (app: Router) => {
 
   route.put(
     '/init',
+    rateLimit({ windowMs: 15 * 60 * 1000, max: 20 }),
     celebrate({
       body: Joi.object({
-        username: Joi.string().required(),
-        password: Joi.string().required(),
+        username: Joi.string().max(1024).required(),
+        password: Joi.string().max(1024).required(),
       }),
     }),
     async (req: Request, res: Response, next: NextFunction) => {
       const logger: Logger = Container.get('logger');
       try {
         const userService = Container.get(UserService);
-        const result = await userService.updateUsernameAndPassword(req.body);
+        const result = await userService.initializeUser(req.body);
         res.send(result);
       } catch (e) {
         return next(e);
diff --git a/back/config/share.ts b/back/config/share.ts
index 8577feea..24c52fa7 100644
--- a/back/config/share.ts
+++ b/back/config/share.ts
@@ -1,3 +1,5 @@
+import { randomInt } from 'crypto';
+
 export function createRandomString(min: number, max: number): string {
   const num = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'];
   const english = [
@@ -65,20 +67,20 @@ export function createRandomString(min: number, max: number): string {
   arr.push(getOne(ENGLISH));
   arr.push(getOne(special));
 
-  const len = min + Math.floor(Math.random() * (max - min + 1));
+  const len = min + randomInt(max - min + 1);
 
   for (let i = 4; i < len; i++) {
-    arr.push(config[Math.floor(Math.random() * config.length)]);
+    arr.push(config[randomInt(config.length)]);
   }
 
   const newArr = [];
   for (let j = 0; j < len; j++) {
-    newArr.push(arr.splice(Math.random() * arr.length, 1)[0]);
+    newArr.push(arr.splice(randomInt(arr.length), 1)[0]);
   }
 
   function getOne(arr: any[]) {
-    return arr[Math.floor(Math.random() * arr.length)];
+    return arr[randomInt(arr.length)];
   }
 
   return newArr.join('');
-}
\ No newline at end of file
+}
diff --git a/back/data/system.ts b/back/data/system.ts
index b61c837b..af20e8ba 100644
--- a/back/data/system.ts
+++ b/back/data/system.ts
@@ -75,6 +75,8 @@ export interface AuthInfo {
   lastaddr: string;
   platform: string;
   isTwoFactorChecking: boolean;
+  twoFactorExpiresAt?: number;
+  lastTwoFactorStep?: number;
   token: string;
   tokens: Record<string, string | TokenInfo[]>;
   twoFactorActivated: boolean;
diff --git a/back/loaders/express.ts b/back/loaders/express.ts
index 12bca534..20c05774 100644
--- a/back/loaders/express.ts
+++ b/back/loaders/express.ts
@@ -48,7 +48,26 @@ export default ({ app }: { app: Application }) => {
   }
 
   app.get(`${config.api.prefix}/env.js`, serveEnv);
-  app.use(`${config.api.prefix}/static`, express.static(config.uploadPath));
+  app.use(
+    `${config.api.prefix}/static`,
+    express.static(config.uploadPath, {
+      setHeaders: (res) => {
+        res.setHeader('X-Content-Type-Options', 'nosniff');
+        res.setHeader('Content-Security-Policy', "sandbox; default-src 'none'");
+      },
+    }),
+  );
+
+  const credentialPaths = ['/api', '/open'].flatMap((prefix) =>
+    ['/user/login', '/user/init', '/user/two-factor/login'].map(
+      (route) => `${prefix}${route}`,
+    ),
+  );
+  app.use(
+    credentialPaths,
+    bodyParser.json({ limit: '16kb' }),
+    bodyParser.urlencoded({ limit: '16kb', extended: false }),
+  );
 
   app.use(bodyParser.json({ limit: '50mb' }));
   app.use(bodyParser.urlencoded({ limit: '50mb', extended: true }));
@@ -123,7 +142,7 @@ export default ({ app }: { app: Application }) => {
     }
 
     const authInfo = await shareStore.getAuthInfo();
-    if (isValidToken(authInfo, headerToken, req.platform)) {
+    if (isValidToken(authInfo, headerToken, req.platform, config.jwt.secret)) {
       return next();
     }
 
diff --git a/back/loaders/sock.ts b/back/loaders/sock.ts
index 5ab0b497..b99b721f 100644
--- a/back/loaders/sock.ts
+++ b/back/loaders/sock.ts
@@ -8,26 +8,44 @@ import { isValidToken } from '../shared/auth';
 import config from '../config';
 
 export default async ({ server }: { server: Server }) => {
-  const echo = sockJs.createServer({ prefix: `${config.baseUrl}/api/ws`, log: () => { } });
+  const echo = sockJs.createServer({
+    prefix: `${config.baseUrl}/api/ws`,
+    log: () => {},
+  });
   const sockService = Container.get(SockService);
 
   echo.on('connection', async (conn) => {
     if (!conn.headers || !conn.url || !conn.pathname) {
       conn.close('404');
+      return;
     }
 
     const authInfo = await shareStore.getAuthInfo();
     const platform = getPlatform(conn.headers['user-agent'] || '') || 'desktop';
     const headerToken = conn.url.replace(`${conn.pathname}?token=`, '');
 
-    if (isValidToken(authInfo, headerToken, platform)) {
+    if (isValidToken(authInfo, headerToken, platform, config.jwt.secret)) {
       sockService.addClient(conn);
+      const checkSession = setInterval(async () => {
+        try {
+          const current = await shareStore.getAuthInfo();
+          if (
+            !isValidToken(current, headerToken, platform, config.jwt.secret)
+          ) {
+            conn.close('401');
+          }
+        } catch {
+          conn.close('401');
+        }
+      }, 1000);
+      checkSession.unref();
 
       conn.on('data', (message) => {
         conn.write(message);
       });
 
       conn.on('close', function () {
+        clearInterval(checkSession);
         sockService.removeClient(conn);
       });
 
diff --git a/back/services/config.ts b/back/services/config.ts
index 0c5ea30a..55335bd3 100644
--- a/back/services/config.ts
+++ b/back/services/config.ts
@@ -1,10 +1,10 @@
-import { Service, Inject } from 'typedi';
-import path, { join } from 'path';
+import { Service } from 'typedi';
 import config from '../config';
 import { getFileContentByName } from '../config/util';
 import { t } from '../shared/i18n';
 import { Response } from 'express';
 import { request } from 'undici';
+import { resolveFileAccess } from '../shared/fileAccess';
 
 @Service()
 export default class ConfigService {
@@ -15,21 +15,13 @@ export default class ConfigService {
     if (!filePath) {
       return res.send({ code: 403, message: t('文件无法访问') });
     }
-    const normalized = path.normalize(filePath);
-    if (normalized.startsWith('..') || path.isAbsolute(normalized)) {
-      return res.send({ code: 403, message: t('文件无法访问') });
-    }
-    const resolvedRoot = path.resolve(config.rootPath, normalized);
-    const resolvedConfig = path.resolve(config.configPath, normalized);
-    const isValidPath =
-      resolvedRoot.startsWith(config.scriptPath) ||
-      resolvedRoot.startsWith(config.configPath) ||
-      resolvedConfig.startsWith(config.scriptPath) ||
-      resolvedConfig.startsWith(config.configPath);
-    if (!isValidPath) {
-      return res.send({ code: 403, message: t('文件无法访问') });
-    }
-    if (config.blackFileList.includes(path.basename(normalized))) {
+    const scriptFile = filePath.startsWith('data/scripts/');
+    const resolved = resolveFileAccess(
+      scriptFile ? config.scriptPath : config.configPath,
+      [scriptFile ? filePath.slice('data/scripts/'.length) : filePath],
+      config.blackFileList,
+    );
+    if (!resolved) {
       return res.send({ code: 403, message: t('文件无法访问') });
     }
 
@@ -38,10 +30,8 @@ export default class ConfigService {
         `https://gitlab.com/whyour/qinglong/-/raw/master/${filePath}`,
       );
       content = await res.body.text();
-    } else if (filePath.startsWith('data/scripts/')) {
-      content = await getFileContentByName(join(config.rootPath, filePath));
     } else {
-      content = await getFileContentByName(join(config.configPath, filePath));
+      content = await getFileContentByName(resolved);
     }
 
     res.send({ code: 200, data: content });
diff --git a/back/services/grpc.ts b/back/services/grpc.ts
index 2a69843f..2e8c6bb6 100644
--- a/back/services/grpc.ts
+++ b/back/services/grpc.ts
@@ -40,7 +40,7 @@ export class GrpcServerService {
       const grpcPort = config.grpcPort;
       const hostsToTry = [
         config.bindHostGrpc,
-        ...(config.bindHostGrpc !== '0.0.0.0' ? ['0.0.0.0'] : [])
+        ...(config.bindHostGrpc === '::' ? ['0.0.0.0'] : [])
       ];
       const bindAsync = promisify(this.server.bindAsync).bind(this.server);
 
diff --git a/back/services/http.ts b/back/services/http.ts
index a47d49c8..f6d6dba3 100644
--- a/back/services/http.ts
+++ b/back/services/http.ts
@@ -12,7 +12,7 @@ export class HttpServerService {
   async initialize(expressApp: express.Application, port: number) {
     const hostsToTry = [
       config.bindHost,
-      ...(config.bindHost !== '0.0.0.0' ? ['0.0.0.0'] : [])
+      ...(config.bindHost === '::' ? ['0.0.0.0'] : [])
     ];
 
     let lastError: Error | null = null;
diff --git a/back/services/log.ts b/back/services/log.ts
index ab3f16e4..cd40116d 100644
--- a/back/services/log.ts
+++ b/back/services/log.ts
@@ -1,3 +1,4 @@
+import { resolveFileAccess } from '../shared/fileAccess';
 import path from 'path';
 import { Inject, Service } from 'typedi';
 import winston from 'winston';
@@ -8,7 +9,10 @@ export default class LogService {
   constructor(@Inject('logger') private logger: winston.Logger) {}
 
   public checkFilePath(filePath: string, fileName: string) {
-    const finalPath = path.resolve(config.logPath, filePath, fileName);
-    return finalPath.startsWith(config.logPath) ? finalPath : '';
+    return resolveFileAccess(
+      config.logPath,
+      [filePath || '', fileName],
+      config.blackFileList,
+    );
   }
 }
diff --git a/back/services/script.ts b/back/services/script.ts
index 52921c6c..ef4a5e2c 100644
--- a/back/services/script.ts
+++ b/back/services/script.ts
@@ -1,3 +1,4 @@
+import { resolveFileAccess } from '../shared/fileAccess';
 import { Service, Inject } from 'typedi';
 import winston from 'winston';
 import path, { join } from 'path';
@@ -65,8 +66,11 @@ export default class ScriptService {
   }
 
   public checkFilePath(filePath: string, fileName: string) {
-    const finalPath = path.resolve(config.scriptPath, filePath, fileName);
-    return finalPath.startsWith(config.scriptPath) ? finalPath : '';
+    return resolveFileAccess(
+      config.scriptPath,
+      [filePath || '', fileName],
+      config.blackFileList,
+    );
   }
 
   public async getFile(filePath: string, fileName: string) {
diff --git a/back/services/user.ts b/back/services/user.ts
index 73ed8dd7..b7f5cf9b 100644
--- a/back/services/user.ts
+++ b/back/services/user.ts
@@ -26,6 +26,13 @@ import isNil from 'lodash/isNil';
 import { shareStore } from '../shared/store';
 import { t, tf } from '../shared/i18n';
 import { getClientIp, normalizeClientIp } from '../shared/clientIp';
+import { isDefaultAuthInfo } from '../shared/auth';
+import {
+  hashPassword,
+  isPasswordHash,
+  verifyPassword,
+} from '../shared/password';
+import { serializeAuthMutation } from '../shared/authMutation';
 
 @Service()
 export default class UserService {
@@ -38,7 +45,15 @@ export default class UserService {
     private sockService: SockService,
   ) {}
 
+  @serializeAuthMutation
   public async login(
+    payloads: { username: string; password: string },
+    req: Request,
+  ): Promise<any> {
+    return this.authenticate(payloads, req);
+  }
+
+  private async authenticate(
     payloads: {
       username: string;
       password: string;
@@ -48,6 +63,9 @@ export default class UserService {
   ): Promise<any> {
     let { username, password } = payloads;
     const content = await this.getAuthInfo();
+    if (isDefaultAuthInfo(content)) {
+      return { code: 450, message: t('请先初始化') };
+    }
     const timestamp = Date.now();
     const ip = getClientIp(req);
     const query = new IP2Region();
@@ -100,14 +118,13 @@ export default class UserService {
       };
     }
 
-    if (
-      username === cUsername &&
-      password === cPassword &&
-      twoFactorActivated &&
-      needTwoFactor
-    ) {
+    const passwordMatches =
+      username === cUsername && (await verifyPassword(password, cPassword));
+
+    if (passwordMatches && twoFactorActivated && needTwoFactor) {
       await this.updateAuthInfo(content, {
         isTwoFactorChecking: true,
+        twoFactorExpiresAt: timestamp + 5 * 60 * 1000,
       });
       return {
         code: 420,
@@ -115,7 +132,7 @@ export default class UserService {
       };
     }
 
-    if (username === cUsername && password === cPassword) {
+    if (passwordMatches) {
       const data = createRandomString(50, 100);
       const expiration = twoFactorActivated ? '60d' : '20d';
       let token = jwt.sign({ data }, config.jwt.secret, {
@@ -138,6 +155,9 @@ export default class UserService {
       );
 
       await this.updateAuthInfo(content, {
+        password: isPasswordHash(cPassword)
+          ? cPassword
+          : await hashPassword(password),
         token,
         tokens: updatedTokens,
         lastlogon: timestamp,
@@ -146,6 +166,7 @@ export default class UserService {
         lastaddr: address,
         platform: req.platform,
         isTwoFactorChecking: false,
+        twoFactorExpiresAt: 0,
       });
       this.notificationService.notify(
         t('登录通知'),
@@ -231,6 +252,7 @@ export default class UserService {
     }
   }
 
+  @serializeAuthMutation
   public async logout(platform: string, tokenValue: string): Promise<any> {
     if (!platform || !tokenValue) {
       this.logger.warn('Invalid logout parameters - empty platform or token');
@@ -291,6 +313,7 @@ export default class UserService {
     );
   }
 
+  @serializeAuthMutation
   public async blockIp(ip: string): Promise<string[]> {
     const authInfo = await this.getAuthInfo();
     const blockedIps = uniq([
@@ -301,6 +324,7 @@ export default class UserService {
     return blockedIps;
   }
 
+  @serializeAuthMutation
   public async unblockIp(ip: string): Promise<string[]> {
     const authInfo = await this.getAuthInfo();
     const normalizedIp = normalizeClientIp(ip);
@@ -316,6 +340,33 @@ export default class UserService {
     return doc;
   }
 
+  @serializeAuthMutation
+  public async initializeUser({
+    username,
+    password,
+  }: {
+    username: string;
+    password: string;
+  }) {
+    const authInfo = await this.getAuthInfo();
+    if (!isDefaultAuthInfo(authInfo)) {
+      return { code: 450, message: t('未知错误') };
+    }
+    if (password === 'admin') {
+      return { code: 400, message: t('密码不能设置为admin') };
+    }
+    await this.updateAuthInfo(authInfo, {
+      username,
+      password: await hashPassword(password),
+      token: '',
+      tokens: {},
+      isTwoFactorChecking: false,
+      twoFactorExpiresAt: 0,
+    });
+    return { code: 200, message: t('更新成功') };
+  }
+
+  @serializeAuthMutation
   public async updateUsernameAndPassword({
     username,
     password,
@@ -327,24 +378,37 @@ export default class UserService {
       return { code: 400, message: t('密码不能设置为admin') };
     }
     const authInfo = await this.getAuthInfo();
-    await this.updateAuthInfo(authInfo, { username, password });
+    await this.updateAuthInfo(authInfo, {
+      username,
+      password: await hashPassword(password),
+      token: '',
+      tokens: {},
+      isTwoFactorChecking: false,
+      twoFactorExpiresAt: 0,
+    });
     return { code: 200, message: t('更新成功') };
   }
 
+  @serializeAuthMutation
   public async updateAvatar(avatar: string) {
     const authInfo = await this.getAuthInfo();
     await this.updateAuthInfo(authInfo, { avatar });
     return { code: 200, data: avatar, message: t('更新成功') };
   }
 
+  @serializeAuthMutation
   public async initTwoFactor() {
     const secret = authenticator.generateSecret();
     const authInfo = await this.getAuthInfo();
+    if (authInfo.twoFactorActivated) {
+      throw new Error(t('请先关闭两步验证'));
+    }
     const otpauth = authenticator.keyuri(authInfo.username, 'qinglong', secret);
     await this.updateAuthInfo(authInfo, { twoFactorSecret: secret });
     return { secret, url: otpauth };
   }
 
+  @serializeAuthMutation
   public async activeTwoFactor(code: string) {
     const authInfo = await this.getAuthInfo();
     const isValid = authenticator.verify({
@@ -352,11 +416,18 @@ export default class UserService {
       secret: authInfo.twoFactorSecret,
     });
     if (isValid) {
-      await this.updateAuthInfo(authInfo, { twoFactorActivated: true });
+      await this.updateAuthInfo(authInfo, {
+        twoFactorActivated: true,
+        token: '',
+        tokens: {},
+        isTwoFactorChecking: false,
+        twoFactorExpiresAt: 0,
+      });
     }
     return isValid;
   }
 
+  @serializeAuthMutation
   public async twoFactorLogin(
     {
       username,
@@ -367,15 +438,28 @@ export default class UserService {
   ) {
     const authInfo = await this.getAuthInfo();
     const { isTwoFactorChecking, twoFactorSecret } = authInfo;
-    if (!isTwoFactorChecking) {
+    const now = Date.now();
+    const retries = authInfo.retries || 0;
+    if (retries > 2 && now - authInfo.lastlogon < Math.pow(3, retries) * 1000) {
+      return { code: 410, message: t('失败次数过多，请稍后重试') };
+    }
+    if (
+      !isTwoFactorChecking ||
+      !authInfo.twoFactorActivated ||
+      !authInfo.twoFactorExpiresAt ||
+      authInfo.twoFactorExpiresAt <= now
+    ) {
       return { code: 450, message: t('未知错误') };
     }
-    const isValid = authenticator.verify({
-      token: code,
-      secret: twoFactorSecret,
-    });
+    const step = Math.floor(now / 30000);
+    const isValid =
+      username === authInfo.username &&
+      (await verifyPassword(password, authInfo.password)) &&
+      authInfo.lastTwoFactorStep !== step &&
+      authenticator.verify({ token: code, secret: twoFactorSecret });
     if (isValid) {
-      return this.login({ username, password }, req, false);
+      await this.updateAuthInfo(authInfo, { lastTwoFactorStep: step });
+      return this.authenticate({ username, password }, req, false);
     } else {
       const ip = getClientIp(req);
       const query = new IP2Region();
@@ -388,6 +472,9 @@ export default class UserService {
           .join(' ');
       }
       await this.updateAuthInfo(authInfo, {
+        retries: retries + 1,
+        lastlogon: now,
+        isTwoFactorChecking: retries + 1 < 5,
         lastip: ip,
         lastaddr: address,
         platform: req.platform,
@@ -396,11 +483,16 @@ export default class UserService {
     }
   }
 
+  @serializeAuthMutation
   public async deactivateTwoFactor() {
     const authInfo = await this.getAuthInfo();
     await this.updateAuthInfo(authInfo, {
       twoFactorActivated: false,
       twoFactorSecret: '',
+      token: '',
+      tokens: {},
+      isTwoFactorChecking: false,
+      twoFactorExpiresAt: 0,
     });
     return true;
   }
@@ -421,6 +513,9 @@ export default class UserService {
       type: AuthDataType.authConfig,
       info: result,
     });
+    if (info.tokens && Object.keys(info.tokens).length === 0) {
+      this.sockService.getClients().forEach((conn) => conn.close('401'));
+    }
   }
 
   public async getNotificationMode(): Promise<NotificationInfo> {
@@ -562,6 +657,7 @@ export default class UserService {
     return undefined;
   }
 
+  @serializeAuthMutation
   public async resetAuthInfo(info: Partial<AuthInfo>) {
     const { retries, twoFactorActivated, password, username } = info;
     if (password === 'admin') {
@@ -578,6 +674,21 @@ export default class UserService {
       (x) => !isNil(x),
     );
 
+    if (password !== undefined) {
+      payload.password = await hashPassword(password);
+    }
+    if (
+      password !== undefined ||
+      username !== undefined ||
+      twoFactorActivated !== undefined
+    ) {
+      Object.assign(payload, {
+        token: '',
+        tokens: {},
+        isTwoFactorChecking: false,
+        twoFactorExpiresAt: 0,
+      });
+    }
     await this.updateAuthInfo(authInfo, payload);
   }
 }
diff --git a/back/shared/auth.ts b/back/shared/auth.ts
index 5bfd694a..2a0e7fcf 100644
--- a/back/shared/auth.ts
+++ b/back/shared/auth.ts
@@ -1,11 +1,8 @@
 import { AuthInfo, TokenInfo } from '../data/system';
+import jwt from 'jsonwebtoken';
 
 export function isDefaultAuthInfo(authInfo: AuthInfo): boolean {
-  return (
-    Object.keys(authInfo).length === 2 &&
-    authInfo.username === 'admin' &&
-    authInfo.password === 'admin'
-  );
+  return authInfo.username === 'admin' && authInfo.password === 'admin';
 }
 
 /**
@@ -21,11 +18,21 @@ export function isValidToken(
   authInfo: AuthInfo | null | undefined,
   headerToken: string,
   platform: string,
+  secret: string,
 ): boolean {
   if (!authInfo || !headerToken) {
     return false;
   }
 
+  try {
+    const claims = jwt.verify(headerToken, secret, { algorithms: ['HS384'] });
+    if (typeof claims === 'string' || typeof claims.exp !== 'number') {
+      return false;
+    }
+  } catch {
+    return false;
+  }
+
   const { token = '', tokens = {} } = authInfo;
 
   // Check legacy token field
@@ -46,7 +53,12 @@ export function isValidToken(
     return headerToken === platformTokens;
   } else if (Array.isArray(platformTokens)) {
     // New format: array of TokenInfo objects
-    return platformTokens.some((t: TokenInfo) => t && t.value === headerToken);
+    return platformTokens.some(
+      (t: TokenInfo) =>
+        t &&
+        t.value === headerToken &&
+        (t.expiration === undefined || t.expiration > Date.now() / 1000),
+    );
   }
 
   // Unexpected type - log warning and reject
diff --git a/back/shared/authMutation.ts b/back/shared/authMutation.ts
new file mode 100644
index 00000000..b041ddd7
--- /dev/null
+++ b/back/shared/authMutation.ts
@@ -0,0 +1,17 @@
+// All account mutations in the HTTP service share one queue. In particular,
+// a login that read old credentials must finish before a password reset revokes
+// its session, and two initialization requests must not both claim the account.
+let pending: Promise<unknown> = Promise.resolve();
+
+export function serializeAuthMutation(
+  _target: object,
+  _key: string,
+  descriptor: PropertyDescriptor,
+) {
+  const method = descriptor.value;
+  descriptor.value = function (this: unknown, ...args: unknown[]) {
+    const result = pending.then(() => method.apply(this, args));
+    pending = result.catch(() => undefined);
+    return result;
+  };
+}
diff --git a/back/shared/fileAccess.ts b/back/shared/fileAccess.ts
new file mode 100644
index 00000000..2cda7e88
--- /dev/null
+++ b/back/shared/fileAccess.ts
@@ -0,0 +1,57 @@
+import fs from 'fs';
+import path from 'path';
+
+function isWithin(root: string, target: string): boolean {
+  const relative = path.relative(root, target);
+  return (
+    relative === '' ||
+    (!relative.startsWith(`..${path.sep}`) &&
+      relative !== '..' &&
+      !path.isAbsolute(relative))
+  );
+}
+
+/** Resolve existing files and not-yet-created children without following an
+ * existing symlink outside the root. Blacklisted directories cover descendants. */
+export function resolveFileAccess(
+  root: string,
+  parts: string[],
+  blacklist: string[] = [],
+): string {
+  if (parts.some((part) => typeof part !== 'string' || part.includes('\0'))) {
+    return '';
+  }
+  const resolvedRoot = path.resolve(root);
+  const target = path.resolve(resolvedRoot, ...parts);
+  if (target === resolvedRoot || !isWithin(resolvedRoot, target)) return '';
+  const isBlocked = (relative: string) =>
+    relative.split(path.sep).some((part) => blacklist.includes(part));
+  if (isBlocked(path.relative(resolvedRoot, target))) return '';
+  try {
+    const realRoot = fs.realpathSync(resolvedRoot);
+    let existing = target;
+    const missing: string[] = [];
+    while (!fs.existsSync(existing)) {
+      // existsSync is false for a dangling symlink; never treat one as absent.
+      try {
+        fs.lstatSync(existing);
+        return '';
+      } catch (error: any) {
+        if (error.code !== 'ENOENT') return '';
+      }
+      if (existing === resolvedRoot) return '';
+      missing.unshift(path.basename(existing));
+      existing = path.dirname(existing);
+    }
+    const realTarget = path.resolve(fs.realpathSync(existing), ...missing);
+    if (
+      !isWithin(realRoot, realTarget) ||
+      isBlocked(path.relative(realRoot, realTarget))
+    ) {
+      return '';
+    }
+    return target;
+  } catch {
+    return '';
+  }
+}
diff --git a/back/shared/password.ts b/back/shared/password.ts
new file mode 100644
index 00000000..f59150df
--- /dev/null
+++ b/back/shared/password.ts
@@ -0,0 +1,30 @@
+import { randomBytes, scrypt, timingSafeEqual } from 'crypto';
+import { promisify } from 'util';
+
+const deriveKey = promisify(scrypt);
+const HASH_PREFIX = 'scrypt$';
+
+export async function hashPassword(password: string): Promise<string> {
+  const salt = randomBytes(16).toString('hex');
+  const key = (await deriveKey(password, salt, 64)) as Buffer;
+  return `${HASH_PREFIX}${salt}$${key.toString('hex')}`;
+}
+
+export function isPasswordHash(password: string): boolean {
+  return /^scrypt\$[a-f0-9]{32}\$[a-f0-9]{128}$/.test(password);
+}
+
+export async function verifyPassword(
+  password: string,
+  stored: string,
+): Promise<boolean> {
+  if (!isPasswordHash(stored)) {
+    // Existing installations migrate after a successful password check.
+    const input = Buffer.from(password);
+    const expected = Buffer.from(stored);
+    return input.length === expected.length && timingSafeEqual(input, expected);
+  }
+  const [, salt, hash] = stored.split('$');
+  const key = (await deriveKey(password, salt, 64)) as Buffer;
+  return timingSafeEqual(key, Buffer.from(hash, 'hex'));
+}
diff --git a/test/back/auth-security.test.cjs b/test/back/auth-security.test.cjs
new file mode 100644
index 00000000..9c483f7f
--- /dev/null
+++ b/test/back/auth-security.test.cjs
@@ -0,0 +1,74 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const path = require('node:path');
+const jwt = require('jsonwebtoken');
+const load = require('../helpers/load-security-module.cjs');
+const { isValidToken } = load(
+  path.join(__dirname, '../../back/shared/auth.ts'),
+);
+const { hashPassword, verifyPassword } = load(
+  path.join(__dirname, '../../back/shared/password.ts'),
+);
+const secret = 'security-test-secret';
+const token = (payload = {}, options = {}) =>
+  jwt.sign(payload, secret, {
+    algorithm: 'HS384',
+    expiresIn: '1h',
+    ...options,
+  });
+const info = (value) => ({ token: value, tokens: {} });
+
+test('valid legacy and platform sessions retain compatibility', () => {
+  const value = token();
+  for (const auth of [
+    info(value),
+    { tokens: { desktop: value } },
+    { tokens: { desktop: [{ value }] } },
+  ]) {
+    assert.equal(isValidToken(auth, value, 'desktop', secret), true);
+  }
+  assert.equal(
+    isValidToken({ tokens: { mobile: value } }, value, 'desktop', secret),
+    false,
+  );
+});
+
+test('session membership never bypasses JWT signature, expiry, algorithm or nbf', () => {
+  const values = [
+    token({}, { expiresIn: -1 }),
+    token({}, { algorithm: 'HS256' }),
+    token({ nbf: Math.floor(Date.now() / 1000) + 60 }),
+    jwt.sign({}, 'wrong-secret', { algorithm: 'HS384', expiresIn: '1h' }),
+    jwt.sign({}, secret, { algorithm: 'HS384' }),
+    'not-a-token',
+  ];
+  for (const value of values)
+    assert.equal(isValidToken(info(value), value, 'desktop', secret), false);
+  assert.equal(isValidToken({ tokens: {} }, token(), 'desktop', secret), false);
+  assert.equal(isValidToken(null, token(), 'desktop', secret), false);
+  assert.equal(isValidToken(info(''), '', 'desktop', secret), false);
+});
+
+test('platform token metadata can shorten but cannot extend JWT expiration', () => {
+  const value = token();
+  assert.equal(
+    isValidToken(
+      { tokens: { desktop: [{ value, expiration: 1 }] } },
+      value,
+      'desktop',
+      secret,
+    ),
+    false,
+  );
+});
+
+test('passwords are salted and legacy plaintext can migrate without changing the password', async () => {
+  const first = await hashPassword('owner-password');
+  const second = await hashPassword('owner-password');
+  assert.notEqual(first, second);
+  assert.equal(await verifyPassword('owner-password', first), true);
+  assert.equal(await verifyPassword('wrong-password', first), false);
+  assert.equal(await verifyPassword(first, first), false);
+  assert.equal(await verifyPassword('old-password', 'old-password'), true);
+  assert.equal(await verifyPassword('wrong', 'old-password'), false);
+});
diff --git a/test/back/file-access-security.test.cjs b/test/back/file-access-security.test.cjs
new file mode 100644
index 00000000..0536ad38
--- /dev/null
+++ b/test/back/file-access-security.test.cjs
@@ -0,0 +1,47 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+const load = require('../helpers/load-security-module.cjs');
+const { resolveFileAccess } = load(
+  path.join(__dirname, '../../back/shared/fileAccess.ts'),
+);
+
+test('file access enforces directory boundaries, blacklist descendants and symlinks', (t) => {
+  const tmp = fs.mkdtempSync(path.join(os.tmpdir(), 'ql-file-security-'));
+  t.after(() => fs.rmSync(tmp, { recursive: true, force: true }));
+  const root = path.join(tmp, 'config');
+  fs.mkdirSync(path.join(root, 'grpc'), { recursive: true });
+  fs.mkdirSync(path.join(tmp, 'config-other'));
+  fs.writeFileSync(path.join(root, 'normal.txt'), 'normal');
+  fs.writeFileSync(path.join(root, 'grpc', 'client.key'), 'test-only');
+  fs.symlinkSync(path.join(tmp, 'config-other'), path.join(root, 'outside'));
+  fs.symlinkSync(path.join(root, 'grpc'), path.join(root, 'alias'));
+  fs.symlinkSync(path.join(root, 'normal.txt'), path.join(root, 'safe-link'));
+  fs.symlinkSync(path.join(tmp, 'missing'), path.join(root, 'dangling'));
+  for (const input of [
+    '../config-other/secret',
+    '/etc/passwd',
+    'grpc/client.key',
+    'alias/client.key',
+    'outside/new.txt',
+    'dangling',
+    'auth.json',
+    'nested/auth.json',
+    '',
+  ]) {
+    assert.equal(
+      resolveFileAccess(root, [input], ['grpc', 'auth.json']),
+      '',
+      input,
+    );
+  }
+  for (const input of ['normal.txt', 'safe-link', 'new-dir/new.txt']) {
+    assert.equal(
+      resolveFileAccess(root, [input], ['grpc']),
+      path.join(root, input),
+      input,
+    );
+  }
+});
diff --git a/test/back/http-security.test.cjs b/test/back/http-security.test.cjs
new file mode 100644
index 00000000..3c9b6b8f
--- /dev/null
+++ b/test/back/http-security.test.cjs
@@ -0,0 +1,213 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+const express = require('express');
+const jwt = require('jsonwebtoken');
+const load = require('../helpers/load-security-module.cjs');
+
+test('HTTP authentication protects init, scopes, expired sessions and config secrets', async (t) => {
+  const tmp = fs.mkdtempSync(path.join(os.tmpdir(), 'ql-http-security-'));
+  for (const dir of ['config/grpc', 'scripts', 'upload', 'tmp'])
+    fs.mkdirSync(path.join(tmp, dir), { recursive: true });
+  fs.writeFileSync(path.join(tmp, 'config/grpc/client.key'), 'SENTINEL');
+  fs.writeFileSync(path.join(tmp, 'config/normal.txt'), 'normal');
+  const secret = 'http-security-test';
+  const valid = jwt.sign({}, secret, { algorithm: 'HS384', expiresIn: '1h' });
+  const expired = jwt.sign({}, secret, { algorithm: 'HS384', expiresIn: -1 });
+  const auth = {
+    username: 'owner',
+    password: 'configured',
+    token: valid,
+    tokens: { desktop: [{ value: expired }] },
+  };
+  const configSource = fs.readFileSync(
+    path.join(__dirname, '../../back/config/index.ts'),
+    'utf8',
+  );
+  const whitelistSource = configSource
+    .slice(configSource.indexOf('apiWhiteList:'))
+    .match(/apiWhiteList:\s*\[([\s\S]*?)\]/)[1];
+  const config = {
+    api: { prefix: '/api' },
+    apiWhiteList: [...whitelistSource.matchAll(/['"]([^'"]+)['"]/g)].map(
+      (x) => x[1],
+    ),
+    jwt: { secret },
+    rootPath: tmp,
+    configPath: path.join(tmp, 'config/'),
+    scriptPath: path.join(tmp, 'scripts/'),
+    uploadPath: path.join(tmp, 'upload'),
+    tmpPath: path.join(tmp, 'tmp'),
+    blackFileList: ['auth.json', 'grpc'],
+    baseUrl: '/panel',
+  };
+  const apps = [
+    {
+      scopes: ['configs'],
+      tokens: [{ value: 'config-app', expiration: Date.now() / 1000 + 3600 }],
+    },
+    {
+      scopes: ['envs'],
+      tokens: [{ value: 'env-app', expiration: Date.now() / 1000 + 3600 }],
+    },
+  ];
+  let initialized = 0;
+  const User = class {};
+  const user = {
+    initializeUser: async () => {
+      initialized++;
+      return { code: 200 };
+    },
+    getAuthInfo: async () => auth,
+  };
+  const mocks = {
+    '../config': config,
+    '../config/util': {
+      getToken: (r) => (r.headers.authorization || '').replace(/^Bearer /, ''),
+      getPlatform: () => 'desktop',
+      getFileContentByName: (p) => fs.promises.readFile(p, 'utf8'),
+    },
+    '../shared/i18n': { t: (x) => x },
+    '../shared/store': {
+      shareStore: { getAuthInfo: async () => auth, getApps: async () => apps },
+    },
+    '../config/serverEnv': { serveEnv: (_req, res) => res.end() },
+    '../services/user': User,
+    '../data/open': {},
+    '../data/system': {},
+    '../shared/utils': {
+      writeFileWithLock: (p, content) => fs.promises.writeFile(p, content),
+    },
+  };
+  const Config = load(path.join(__dirname, '../../back/services/config.ts'), {
+    ...mocks,
+    typedi: { Service: () => (x) => x },
+  }).default;
+  const configService = new Config();
+  mocks['../services/config'] = Config;
+  mocks.typedi = {
+    Container: { get: (x) => (x === User ? user : configService) },
+  };
+  mocks['../api'] = () => {
+    const router = express.Router();
+    load(path.join(__dirname, '../../back/api/user.ts'), mocks).default(router);
+    load(path.join(__dirname, '../../back/api/config.ts'), mocks).default(
+      router,
+    );
+    router.get('/envs', (_req, res) => res.json({ code: 200 }));
+    return router;
+  };
+  const app = express();
+  load(path.join(__dirname, '../../back/loaders/express.ts'), mocks).default({
+    app,
+  });
+  const server = app.listen(0, '127.0.0.1');
+  t.after(async () => {
+    await new Promise((resolve) => server.close(resolve));
+    fs.rmSync(tmp, { recursive: true, force: true });
+  });
+  await new Promise((resolve, reject) => {
+    server.on('listening', resolve);
+    server.on('error', reject);
+  });
+  const request = async (url, token, method = 'GET', body) => {
+    const response = await fetch(
+      `http://127.0.0.1:${server.address().port}${url}`,
+      {
+        method,
+        headers: {
+          ...(token ? { Authorization: `Bearer ${token}` } : {}),
+          'Content-Type': 'application/json',
+        },
+        ...(body ? { body: JSON.stringify(body) } : {}),
+      },
+    );
+    return { status: response.status, body: await response.json() };
+  };
+  for (const url of [
+    '/api/user/init',
+    '/open/user/init',
+    '/panel/api/user/init',
+    '/panel/open/user/init',
+  ]) {
+    const response = await request(url, undefined, 'PUT', {
+      username: 'attacker',
+      password: 'changed',
+    });
+    assert.equal(response.body.code, 450, url);
+  }
+  assert.equal(initialized, 0);
+  assert.equal(
+    (
+      await request('/api/user/login', undefined, 'POST', {
+        username: 'x',
+        password: 'x'.repeat(20000),
+      })
+    ).status,
+    413,
+  );
+  fs.writeFileSync(
+    path.join(tmp, 'upload/legacy.html'),
+    '<script>window.test=1</script>',
+  );
+  const legacyUpload = await fetch(
+    `http://127.0.0.1:${server.address().port}/api/static/legacy.html`,
+  );
+  assert.equal(legacyUpload.headers.get('x-content-type-options'), 'nosniff');
+  assert.equal(
+    legacyUpload.headers.get('content-security-policy'),
+    "sandbox; default-src 'none'",
+  );
+  for (const prefix of ['/api', '/open', '/panel/api', '/panel/open']) {
+    assert.equal(
+      (await request(`${prefix}/envs`, expired)).status,
+      401,
+      prefix,
+    );
+    assert.equal(
+      (await request(`${prefix}/envs`, valid)).body.code,
+      200,
+      prefix,
+    );
+    assert.equal((await request(`${prefix}/envs`)).status, 401, prefix);
+  }
+  assert.equal((await request('/open/envs', 'env-app')).body.code, 200);
+  assert.equal(
+    (await request('/open/configs/detail?path=normal.txt', 'env-app')).status,
+    401,
+  );
+  assert.equal(
+    (await request('/open/configs/detail?path=normal.txt', 'config-app')).body
+      .data,
+    'normal',
+  );
+  assert.equal(
+    (await request('/open/configs/detail?path=grpc/client.key', 'config-app'))
+      .body.code,
+    403,
+  );
+  assert.equal(
+    (
+      await request('/open/configs/save', 'config-app', 'POST', {
+        name: 'grpc/client.key',
+        content: 'changed',
+      })
+    ).body.code,
+    403,
+  );
+  assert.equal(
+    fs.readFileSync(path.join(tmp, 'config/grpc/client.key'), 'utf8'),
+    'SENTINEL',
+  );
+  assert.equal(
+    (
+      await request('/Api/user/init', undefined, 'PUT', {
+        username: 'x',
+        password: 'y',
+      })
+    ).status,
+    400,
+  );
+});
diff --git a/test/back/listen-security.test.cjs b/test/back/listen-security.test.cjs
new file mode 100644
index 00000000..f21092ab
--- /dev/null
+++ b/test/back/listen-security.test.cjs
@@ -0,0 +1,67 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const path = require('node:path');
+const load = require('../helpers/load-security-module.cjs');
+const logger = { debug() {}, warn() {}, error() {} };
+
+for (const host of ['127.0.0.1', '::1', '192.0.2.1', '::']) {
+  test(`HTTP binding ${host} never broadens an explicit private address`, async () => {
+    const Http = load(path.join(__dirname, '../../back/services/http.ts'), {
+      '../config': { bindHost: host },
+      '../loaders/logger': logger,
+      './metrics': { metricsService: { record() {} } },
+      typedi: { Service: () => (x) => x },
+    }).HttpServerService;
+    const instance = new Http();
+    const attempted = [];
+    instance.tryListen = async (_app, _port, address) => {
+      attempted.push(address);
+      throw new Error('unavailable');
+    };
+    await assert.rejects(instance.initialize({}, 5700));
+    assert.deepEqual(attempted, host === '::' ? ['::', '0.0.0.0'] : [host]);
+  });
+  test(`gRPC binding ${host} never broadens an explicit private address`, async () => {
+    const attempted = [];
+    const Grpc = load(path.join(__dirname, '../../back/services/grpc.ts'), {
+      '../config': { bindHostGrpc: host, grpcPort: 5500 },
+      '../loaders/logger': logger,
+      './metrics': { metricsService: { record() {} } },
+      typedi: { Service: () => (x) => x },
+      '@grpc/grpc-js': {
+        Server: class {
+          addService() {}
+          bindAsync(address, _credentials, cb) {
+            attempted.push(address);
+            cb(new Error('unavailable'));
+          }
+        },
+        ServerCredentials: {
+          createSsl(_ca, _certs, requireClientCert) {
+            assert.equal(requireClientCert, true);
+            return {};
+          },
+        },
+      },
+      '../protos/cron': { CronService: {} },
+      '../protos/health': { HealthService: {} },
+      '../protos/api': { ApiService: {} },
+      '../schedule/addCron': {},
+      '../schedule/delCron': {},
+      '../schedule/health': {},
+      '../schedule/api': {},
+      '../config/grpcCerts': {
+        initGrpcCerts: async () => ({
+          caCert: 'test',
+          serverCert: 'test',
+          serverKey: 'test',
+        }),
+      },
+    }).GrpcServerService;
+    await assert.rejects(new Grpc().initialize());
+    assert.deepEqual(
+      attempted,
+      host === '::' ? ['[::]:5500', '0.0.0.0:5500'] : [`${host}:5500`],
+    );
+  });
+}
diff --git a/test/back/sock-security.test.cjs b/test/back/sock-security.test.cjs
new file mode 100644
index 00000000..e7ba59bf
--- /dev/null
+++ b/test/back/sock-security.test.cjs
@@ -0,0 +1,72 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const path = require('node:path');
+const { EventEmitter } = require('node:events');
+const jwt = require('jsonwebtoken');
+const load = require('../helpers/load-security-module.cjs');
+
+test('WebSocket connections reject expired tokens and close when sessions are revoked', async () => {
+  const secret = 'sock-test';
+  const valid = jwt.sign({}, secret, { algorithm: 'HS384', expiresIn: '1h' });
+  const expired = jwt.sign({}, secret, { algorithm: 'HS384', expiresIn: -1 });
+  let auth = { token: valid, tokens: { desktop: [{ value: expired }] } };
+  let onConnection;
+  const clients = new Set();
+  const Sock = class {};
+  const loader = load(path.join(__dirname, '../../back/loaders/sock.ts'), {
+    sockjs: {
+      createServer: () => ({
+        on: (_event, fn) => {
+          onConnection = fn;
+        },
+        installHandlers() {},
+      }),
+    },
+    typedi: {
+      Container: {
+        get: () => ({
+          addClient: (c) => clients.add(c),
+          removeClient: (c) => clients.delete(c),
+        }),
+      },
+    },
+    '../services/sock': Sock,
+    '../config': { jwt: { secret }, baseUrl: '' },
+    '../config/util': { getPlatform: () => 'desktop' },
+    '../shared/store': { shareStore: { getAuthInfo: async () => auth } },
+  }).default;
+  await loader({ server: {} });
+  const connection = (token) => {
+    const c = new EventEmitter();
+    Object.assign(c, {
+      headers: {},
+      pathname: '/api/ws/a/b/websocket',
+      url: `/api/ws/a/b/websocket?token=${token}`,
+      close() {
+        this.closed = true;
+        this.emit('close');
+      },
+      write() {},
+    });
+    return c;
+  };
+  const rejected = connection(expired);
+  await onConnection(rejected);
+  assert.equal(rejected.closed, true);
+  assert.equal(clients.size, 0);
+  const accepted = connection(valid);
+  await onConnection(accepted);
+  assert.equal(clients.size, 1);
+  auth = { token: '', tokens: {} };
+  await new Promise((resolve, reject) => {
+    const timeout = setTimeout(() => {
+      accepted.close();
+      reject(new Error('revoked socket remained open'));
+    }, 3000);
+    accepted.once('close', () => {
+      clearTimeout(timeout);
+      resolve();
+    });
+  });
+  assert.equal(clients.size, 0);
+});
diff --git a/test/back/user-api.test.cjs b/test/back/user-api.test.cjs
index 42e6a69f..f0c275a6 100644
--- a/test/back/user-api.test.cjs
+++ b/test/back/user-api.test.cjs
@@ -46,7 +46,7 @@ test('initialization returns the username and password validation result', async
     paths: [],
   };
   Container.get = () => ({
-    updateUsernameAndPassword: async () => ({
+    initializeUser: async () => ({
       code: 400,
       message: 'password rejected',
     }),
diff --git a/test/back/user-security.test.cjs b/test/back/user-security.test.cjs
new file mode 100644
index 00000000..963aadcd
--- /dev/null
+++ b/test/back/user-security.test.cjs
@@ -0,0 +1,248 @@
+const assert = require('node:assert/strict');
+const test = require('node:test');
+const path = require('node:path');
+const jwt = require('jsonwebtoken');
+const { authenticator } = require('@otplib/preset-default');
+const load = require('../helpers/load-security-module.cjs');
+const { verifyPassword, isPasswordHash } = load(
+  path.join(__dirname, '../../back/shared/password.ts'),
+);
+const req = {
+  platform: 'desktop',
+  headers: {},
+  socket: { remoteAddress: '127.0.0.1' },
+};
+
+function fixture(initial) {
+  let auth = structuredClone(initial);
+  let closed = 0;
+  const model = {
+    findOne: async () => ({ id: 1 }),
+    update: async () => [1, [{}]],
+    create: async (x) => x,
+    findAll: async () => [],
+    destroy: async () => {},
+  };
+  const mocks = {
+    typedi: { Service: () => (x) => x, Inject: () => () => {} },
+    '../config': { jwt: { secret: 'test-secret' }, maxTokensPerPlatform: 10 },
+    '../data/system': {
+      AuthDataType: { authConfig: 'authConfig', loginLog: 'loginLog' },
+      LoginStatus: { fail: 0, success: 1 },
+      SystemModel: model,
+    },
+    '../config/util': {
+      createRandomString: () =>
+        require('node:crypto').randomBytes(32).toString('hex'),
+    },
+    './notify': class {},
+    './schedule': class {},
+    './sock': class {},
+    '../shared/store': {
+      shareStore: {
+        getAuthInfo: async () => auth,
+        updateAuthInfo: async (x) => {
+          auth = x;
+        },
+      },
+    },
+    '../shared/i18n': { t: (x) => x, tf: (x, y) => x.replace('%s', y) },
+    '../shared/clientIp': {
+      getClientIp: () => '127.0.0.1',
+      normalizeClientIp: (x) => x,
+    },
+    ip2region: class {
+      search() {
+        return null;
+      }
+    },
+  };
+  const User = load(
+    path.join(__dirname, '../../back/services/user.ts'),
+    mocks,
+  ).default;
+  const user = new User(
+    { warn() {}, info() {} },
+    {},
+    { getClients: () => [{ close: () => closed++ }] },
+  );
+  user.notificationService = { notify() {} };
+  return {
+    user,
+    get auth() {
+      return auth;
+    },
+    get closed() {
+      return closed;
+    },
+  };
+}
+const initialized = () => ({
+  username: 'owner',
+  password: 'old-password',
+  token: 'stolen-token',
+  tokens: { desktop: [{ value: 'stolen-token' }] },
+  retries: 0,
+  lastlogon: 0,
+});
+
+test('initialization checks state inside a serialized mutation', async () => {
+  const f = fixture({ username: 'admin', password: 'admin' });
+  assert.equal(
+    (await f.user.login({ username: 'admin', password: 'admin' }, req)).code,
+    450,
+  );
+  assert.deepEqual(f.auth, { username: 'admin', password: 'admin' });
+  const results = await Promise.all([
+    f.user.initializeUser({ username: 'owner', password: 'first-password' }),
+    f.user.initializeUser({
+      username: 'attacker',
+      password: 'second-password',
+    }),
+  ]);
+  assert.deepEqual(
+    results.map((x) => x.code),
+    [200, 450],
+  );
+  assert.equal(f.auth.username, 'owner');
+  assert.equal(await verifyPassword('first-password', f.auth.password), true);
+  assert.equal(
+    (
+      await f.user.initializeUser({
+        username: 'attacker',
+        password: 'third-password',
+      })
+    ).code,
+    450,
+  );
+});
+
+test('password change revokes sessions and closes connected clients', async () => {
+  const f = fixture(initialized());
+  await f.user.updateUsernameAndPassword({
+    username: 'owner',
+    password: 'new-password',
+  });
+  assert.equal(f.auth.token, '');
+  assert.deepEqual(f.auth.tokens, {});
+  assert.equal(f.closed, 1);
+  assert.equal(await verifyPassword('new-password', f.auth.password), true);
+  assert.equal(
+    (await f.user.login({ username: 'owner', password: 'old-password' }, req))
+      .code,
+    400,
+  );
+  const login = await f.user.login(
+    { username: 'owner', password: 'new-password' },
+    req,
+  );
+  assert.equal(login.code, 200);
+  jwt.verify(login.data.token, 'test-secret', { algorithms: ['HS384'] });
+});
+
+test('a concurrent old-password login cannot restore a session after reset', async () => {
+  const f = fixture(initialized());
+  const results = await Promise.all([
+    f.user.login({ username: 'owner', password: 'old-password' }, req),
+    f.user.resetAuthInfo({ password: 'new-password' }),
+  ]);
+  assert.equal(results[0].code, 200);
+  assert.equal(f.auth.token, '');
+  assert.deepEqual(f.auth.tokens, {});
+  assert.equal(await verifyPassword('new-password', f.auth.password), true);
+});
+
+test('legacy plaintext migrates after a successful login', async () => {
+  const f = fixture(initialized());
+  assert.equal(
+    (await f.user.login({ username: 'owner', password: 'old-password' }, req))
+      .code,
+    200,
+  );
+  assert.equal(isPasswordHash(f.auth.password), true);
+  assert.equal(await verifyPassword('old-password', f.auth.password), true);
+});
+
+test('TOTP failures are counted serially and further attempts are throttled', async () => {
+  const secret = authenticator.generateSecret();
+  const f = fixture({
+    ...initialized(),
+    twoFactorActivated: true,
+    twoFactorSecret: secret,
+  });
+  assert.equal(
+    (await f.user.login({ username: 'owner', password: 'old-password' }, req))
+      .code,
+    420,
+  );
+  const badCode =
+    authenticator.generate(secret) === '000000' ? '111111' : '000000';
+  const results = await Promise.all(
+    Array.from({ length: 120 }, () =>
+      f.user.twoFactorLogin(
+        { username: 'owner', password: 'old-password', code: badCode },
+        req,
+      ),
+    ),
+  );
+  assert.equal(f.auth.retries, 3);
+  assert.equal(results.filter((x) => x.code === 430).length, 3);
+  assert.equal(results.filter((x) => x.code === 410).length, 117);
+});
+
+test('TOTP challenge expires and valid codes cannot be reused in the same step', async () => {
+  const secret = authenticator.generateSecret();
+  const f = fixture({
+    ...initialized(),
+    twoFactorActivated: true,
+    twoFactorSecret: secret,
+  });
+  await f.user.login({ username: 'owner', password: 'old-password' }, req);
+  f.auth.twoFactorExpiresAt = Date.now() - 1;
+  const payload = {
+    username: 'owner',
+    password: 'old-password',
+    code: authenticator.generate(secret),
+  };
+  assert.equal((await f.user.twoFactorLogin(payload, req)).code, 450);
+  await f.user.login({ username: 'owner', password: 'old-password' }, req);
+  assert.equal((await f.user.twoFactorLogin(payload, req)).code, 200);
+  await f.user.login({ username: 'owner', password: 'old-password' }, req);
+  assert.equal((await f.user.twoFactorLogin(payload, req)).code, 430);
+});
+
+test('active two-factor secret cannot be silently replaced and disabling revokes sessions', async () => {
+  const f = fixture({
+    ...initialized(),
+    twoFactorActivated: true,
+    twoFactorSecret: authenticator.generateSecret(),
+  });
+  await assert.rejects(f.user.initTwoFactor());
+  await f.user.deactivateTwoFactor();
+  assert.equal(f.auth.token, '');
+  assert.deepEqual(f.auth.tokens, {});
+  assert.equal(f.auth.twoFactorSecret, '');
+});
+
+test('default credentials with historical metadata still require initialization', async () => {
+  const f = fixture({
+    username: 'admin',
+    password: 'admin',
+    retries: 1,
+    token: 'old-default-session',
+  });
+  assert.equal(
+    (await f.user.login({ username: 'admin', password: 'admin' }, req)).code,
+    450,
+  );
+  assert.equal(
+    (
+      await f.user.initializeUser({
+        username: 'owner',
+        password: 'new-password',
+      })
+    ).code,
+    200,
+  );
+  assert.equal(f.auth.token, '');
+});
diff --git a/test/helpers/load-security-module.cjs b/test/helpers/load-security-module.cjs
new file mode 100644
index 00000000..fd286ab6
--- /dev/null
+++ b/test/helpers/load-security-module.cjs
@@ -0,0 +1,42 @@
+const fs = require('node:fs');
+const path = require('node:path');
+const { createRequire } = require('node:module');
+const ts = require('typescript');
+
+module.exports = function loadSecurityModule(
+  file,
+  mocks = {},
+  cache = new Map(),
+) {
+  file = path.resolve(file);
+  if (cache.has(file)) return cache.get(file).exports;
+  const module = { exports: {} };
+  cache.set(file, module);
+  const localRequire = createRequire(file);
+  const requireModule = (name) => {
+    if (Object.hasOwn(mocks, name)) return mocks[name];
+    if (name.startsWith('.')) {
+      const target = path.resolve(path.dirname(file), name);
+      if (fs.existsSync(`${target}.ts`)) {
+        return loadSecurityModule(`${target}.ts`, mocks, cache);
+      }
+    }
+    return localRequire(name);
+  };
+  const { outputText } = ts.transpileModule(fs.readFileSync(file, 'utf8'), {
+    compilerOptions: {
+      module: ts.ModuleKind.CommonJS,
+      target: ts.ScriptTarget.ES2020,
+      experimentalDecorators: true,
+      esModuleInterop: true,
+    },
+  });
+  // Use the host realm: express-unless checks RegExp with instanceof.
+  new Function('require', 'module', 'exports', '__dirname', outputText)(
+    requireModule,
+    module,
+    module.exports,
+    path.dirname(file),
+  );
+  return module.exports;
+};