Next.js Security Vulnerabilities and Attack Vectors 2025

Next.js has revolutionized React development with its powerful features like Server-Side Rendering (SSR), Static Site Generation (SSG), API routes, and middleware. However, these powerful features also introduce unique security challenges. In this comprehensive 2025 guide, we'll explore Next.js-specific vulnerabilities, common attack vectors, and advanced protection strategies that go beyond general web security practices.

Next.js Security Landscape 2025

Next.js applications are particularly attractive to attackers because they often handle:

Server-side rendering with sensitive data
API routes processing user inputs
Authentication and authorization logic
Static generation with dynamic content
Middleware intercepting all requests

Critical Next.js Vulnerabilities (2024-2025)

1. Next.js 14.0.0 - Server-Side Request Forgery (SSRF) in Image Optimization

A critical SSRF vulnerability allowed attackers to make internal network requests through Next.js's image optimization API.

Vulnerable Configuration:

// next.config.js - VULNERABLE
module.exports = {
  images: {
    domains: ['*'], // TOO PERMISSIVE
    remotePatterns: [
      {
        protocol: 'https',
        hostname: '**', // ALLOWS ANY DOMAIN
      }
    ]
  }
}

Secure Configuration:

// next.config.js - SECURE
module.exports = {
  images: {
    domains: ['trusted-cdn.com', 'my-domain.com'],
    remotePatterns: [
      {
        protocol: 'https',
        hostname: 'cdn.myapp.com',
        port: '',
        pathname: '/images/**',
      },
      {
        protocol: 'https',
        hostname: 'avatars.githubusercontent.com',
        port: '',
        pathname: '/u/**',
      }
    ],
    dangerouslyAllowSVG: false,
    contentSecurityPolicy: "default-src 'self'; script-src 'none'; sandbox;",
  }
}

2. API Route Injection Vulnerability (2024)

Attackers could inject malicious code through API route parameters, leading to remote code execution.

Vulnerable API Route:

// pages/api/user/[id].js or app/api/user/[id]/route.js - VULNERABLE
export default async function handler(req, res) {
  const { id } = req.query;

  // DANGEROUS: Direct string interpolation
  const query = `SELECT * FROM users WHERE id = '${id}'`;

  const result = await db.query(query);
  res.status(200).json(result);
}

Secure API Route:

// pages/api/user/[id].js or app/api/user/[id]/route.js - SECURE
import sql from '@/lib/db';

export default async function handler(req, res) {
  const { id } = req.query;

  // Validate input
  if (!id || typeof id !== 'string' || id.length > 50) {
    return res.status(400).json({ error: 'Invalid user ID' });
  }

  // Use parameterized queries
  const result = await sql`
    SELECT id, name, email FROM users
    WHERE id = ${id}
    AND deleted_at IS NULL
  `;

  if (result.length === 0) {
    return res.status(404).json({ error: 'User not found' });
  }

  res.status(200).json(result[0]);
}

3. Middleware Authentication Bypass (2024)

Next.js middleware could be bypassed using specific request patterns, allowing unauthorized access to protected routes.

Vulnerable Middleware:

// middleware.js - VULNERABLE
import { NextResponse } from 'next/server';

export function middleware(request) {
  const token = request.cookies.get('auth-token');

  if (!token) {
    return NextResponse.redirect(new URL('/login', request.url));
  }

  // MISSING: Token validation
  return NextResponse.next();
}

export const config = {
  matcher: ['/dashboard/:path*', '/api/private/:path*'],
};

Secure Middleware:

// middleware.js - SECURE
import { NextResponse } from 'next/server';
import { verifyToken } from '@/lib/auth';

export async function middleware(request) {
  const token = request.cookies.get('auth-token')?.value;

  if (!token) {
    return NextResponse.redirect(new URL('/login', request.url));
  }

  try {
    // Validate token
    const payload = await verifyToken(token);

    // Check token expiration
    if (payload.exp < Date.now() / 1000) {
      return NextResponse.redirect(new URL('/login', request.url));
    }

    // Add user info to headers for API routes
    const requestHeaders = new Headers(request.headers);
    requestHeaders.set('x-user-id', payload.userId);
    requestHeaders.set('x-user-role', payload.role);

    return NextResponse.next({
      request: {
        headers: requestHeaders,
      },
    });
  } catch (error) {
    console.error('Token verification failed:', error);
    return NextResponse.redirect(new URL('/login', request.url));
  }
}

export const config = {
  matcher: [
    '/dashboard/:path*',
    '/api/private/:path*',
    '/((?!login|register|_next/static|_next/image|favicon.ico).*)',
  ],
};

Next.js-Specific Attack Vectors

1. Server-Side Rendering (SSR) Injection Attacks

Dynamic Import Injection:

// VULNERABLE - User-controlled dynamic imports
const ComponentPage = ({ componentName }) => {
  const Component = dynamic(() => import(`../components/${componentName}`));
  return <Component />;
};

Secure Alternative:

// SECURE - Whitelist allowed components
const ALLOWED_COMPONENTS = {
  'Hero': () => import('../components/Hero'),
  'About': () => import('../components/About'),
  'Contact': () => import('../components/Contact'),
};

const ComponentPage = ({ componentName }) => {
  const ComponentLoader = ALLOWED_COMPONENTS[componentName];

  if (!ComponentLoader) {
    return <div>Component not found</div>;
  }

  const Component = dynamic(ComponentLoader);
  return <Component />;
};

2. Static Site Generation (SSG) Data Poisoning

Attackers can poison statically generated pages through malicious data sources.

Vulnerable getStaticProps:

// pages/blog/[slug].js - VULNERABLE
export async function getStaticProps({ params }) {
  const { slug } = params;

  // DANGEROUS: No input validation
  const post = await fetch(`https://api.external-blog.com/posts/${slug}`)
    .then(res => res.json());

  return {
    props: {
      post,
    },
    revalidate: 3600,
  };
}

Secure getStaticProps:

// pages/blog/[slug].js - SECURE
export async function getStaticProps({ params }) {
  const { slug } = params;

  // Validate slug format
  if (!slug || typeof slug !== 'string' || !/^[a-zA-Z0-9-]+$/.test(slug)) {
    return {
      notFound: true,
    };
  }

  try {
    const response = await fetch(`https://api.internal-blog.com/posts/${slug}`, {
      headers: {
        'Authorization': `Bearer ${process.env.INTERNAL_API_KEY}`,
        'User-Agent': 'Next.js-SSG/1.0',
      },
      // Set timeout
      signal: AbortSignal.timeout(5000),
    });

    if (!response.ok) {
      throw new Error(`API returned ${response.status}`);
    }

    const post = await response.json();

    // Validate post structure
    if (!post.title || !post.content || !Array.isArray(post.tags)) {
      throw new Error('Invalid post structure');
    }

    // Sanitize content
    const sanitizedPost = {
      ...post,
      title: sanitizeHtml(post.title, { allowedTags: [] }),
      content: sanitizeHtml(post.content, {
        allowedTags: ['p', 'br', 'strong', 'em', 'h1', 'h2', 'h3'],
      }),
      tags: post.tags.filter(tag => typeof tag === 'string' && tag.length < 50),
    };

    return {
      props: {
        post: sanitizedPost,
      },
      revalidate: 3600,
    };
  } catch (error) {
    console.error('Error fetching post:', error);
    return {
      notFound: true,
    };
  }
}

export async function getStaticPaths() {
  // Generate paths for known posts only
  const posts = await fetch('https://api.internal-blog.com/posts?limit=100')
    .then(res => res.json());

  return {
    paths: posts.map(post => ({
      params: { slug: post.slug },
    })),
    fallback: 'blocking', // More secure than 'true'
  };
}

3. API Route Path Traversal

File system access through API route parameters.

Vulnerable API Route:

// pages/api/files/[...path].js - VULNERABLE
import fs from 'fs';
import path from 'path';

export default function handler(req, res) {
  const filePath = path.join(process.cwd(), 'uploads', ...req.query.path);

  // DANGEROUS: No path validation
  const content = fs.readFileSync(filePath);
  res.status(200).send(content);
}

Secure API Route:

// pages/api/files/[...path].js - SECURE
import fs from 'fs';
import path from 'path';

export default function handler(req, res) {
  const { path: pathSegments } = req.query;

  // Validate path segments
  if (!Array.isArray(pathSegments) || pathSegments.length === 0) {
    return res.status(400).json({ error: 'Invalid path' });
  }

  // Validate each segment
  for (const segment of pathSegments) {
    if (typeof segment !== 'string' ||
        segment.length === 0 ||
        segment.length > 100 ||
        /[\/:*?"<>|]/.test(segment) ||
        segment === '.' ||
        segment === '..') {
      return res.status(400).json({ error: 'Invalid path segment' });
    }
  }

  const safePath = path.join(process.cwd(), 'uploads', ...pathSegments);
  const resolvedPath = path.resolve(safePath);

  // Ensure path is within uploads directory
  if (!resolvedPath.startsWith(path.resolve(process.cwd(), 'uploads'))) {
    return res.status(403).json({ error: 'Access denied' });
  }

  // Check file extension whitelist
  const allowedExtensions = ['.jpg', '.png', '.pdf', '.txt'];
  const ext = path.extname(resolvedPath).toLowerCase();

  if (!allowedExtensions.includes(ext)) {
    return res.status(403).json({ error: 'File type not allowed' });
  }

  try {
    const stat = fs.statSync(resolvedPath);

    // Check file size limits
    if (stat.size > 10 * 1024 * 1024) { // 10MB limit
      return res.status(413).json({ error: 'File too large' });
    }

    const content = fs.readFileSync(resolvedPath);

    // Set appropriate content type
    const contentType = ext === '.pdf' ? 'application/pdf' :
                       ext === '.txt' ? 'text/plain' :
                       'application/octet-stream';

    res.setHeader('Content-Type', contentType);
    res.setHeader('Content-Length', stat.size);
    res.status(200).send(content);
  } catch (error) {
    if (error.code === 'ENOENT') {
      return res.status(404).json({ error: 'File not found' });
    }
    console.error('File read error:', error);
    return res.status(500).json({ error: 'Internal server error' });
  }
}

4. Environment Variable Exposure

Next.js applications can accidentally expose sensitive environment variables.

Vulnerable Client-Side Code:

// pages/settings.js - VULNERABLE
export default function Settings() {
  // DANGEROUS: Client-side access to sensitive data
  const apiKey = process.env.API_KEY; // This will be undefined/null
  const dbPassword = process.env.DATABASE_PASSWORD;

  return (
    <div>
      <p>API Key: {apiKey}</p>
      <p>DB Password: {dbPassword}</p>
    </div>
  );
}

Secure Environment Handling:

// .env.local
NEXT_PUBLIC_API_URL=https://api.myapp.com
DATABASE_URL=postgresql://user:password@localhost:5432/myapp
JWT_SECRET=your-super-secure-secret
STRIPE_PUBLISHABLE_KEY=pk_live_...
STRIPE_SECRET_KEY=sk_live_...

// pages/settings.js - SECURE
import { loadStripe } from '@stripe/stripe-js';

// Client-side: Only public keys
const stripePromise = loadStripe(process.env.NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY);

export default function Settings() {
  return (
    <div>
      {/* Only expose necessary public information */}
      <p>API URL: {process.env.NEXT_PUBLIC_API_URL}</p>
    </div>
  );
}

// Server-side: Use all environment variables securely
export async function getServerSideProps() {
  // This runs on server, environment variables are available
  const stripe = require('stripe')(process.env.STRIPE_SECRET_KEY);

  try {
    const paymentMethods = await stripe.paymentMethods.list({
      customer: userId,
      type: 'card',
    });

    return {
      props: {
        paymentMethods: paymentMethods.data,
      },
    };
  } catch (error) {
    return {
      props: {
        error: 'Failed to load payment methods',
      },
    };
  }
}

5. Next.js Image Component Vulnerabilities

The Next.js Image component can be exploited for SSRF attacks.

Vulnerable Image Usage:

// VULNERABLE - User-controlled image URLs
import Image from 'next/image';

export default function UserProfile({ user }) {
  return (
    <Image
      src={user.avatarUrl} // DANGEROUS: User-controlled URL
      alt="User avatar"
      width={100}
      height={100}
    />
  );
}

Secure Image Handling:

// SECURE - Validate and proxy images
import Image from 'next/image';

export default function UserProfile({ user }) {
  // Validate image URL
  const isValidImageUrl = (url) => {
    try {
      const parsedUrl = new URL(url);
      return (
        (parsedUrl.protocol === 'https:' || parsedUrl.protocol === 'http:') &&
        ['avatars.githubusercontent.com', 'cdn.myapp.com'].includes(parsedUrl.hostname)
      );
    } catch {
      return false;
    }
  };

  const imageUrl = isValidImageUrl(user.avatarUrl)
    ? user.avatarUrl
    : '/default-avatar.png';

  return (
    <Image
      src={imageUrl}
      alt="User avatar"
      width={100}
      height={100}
      placeholder="blur"
      blurDataURL="data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQ..."
    />
  );
}

Advanced Next.js Security Patterns

1. Rate Limiting for API Routes

Protect against brute force and DoS attacks.

API Route with Rate Limiting:

// lib/rate-limit.js
import rateLimit from 'express-rate-limit';

const limiter = rateLimit({
  windowMs: 15 * 60 * 1000, // 15 minutes
  max: 100, // Limit each IP to 100 requests per windowMs
  message: {
    error: 'Too many requests from this IP, please try again later.',
  },
  standardHeaders: true,
  legacyHeaders: false,
});

// For sensitive operations
const strictLimiter = rateLimit({
  windowMs: 60 * 1000, // 1 minute
  max: 5, // 5 requests per minute
  message: {
    error: 'Too many attempts, please try again in a minute.',
  },
});

export { limiter, strictLimiter };

// pages/api/auth/login.js
import { strictLimiter } from '@/lib/rate-limit';

export default strictLimiter(async function handler(req, res) {
  if (req.method !== 'POST') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  const { email, password } = req.body;

  // Validate input
  if (!email || !password) {
    return res.status(400).json({ error: 'Email and password required' });
  }

  // Authenticate user
  try {
    const user = await authenticateUser(email, password);

    // Generate token
    const token = generateToken(user);

    res.status(200).json({
      token,
      user: {
        id: user.id,
        email: user.email,
        name: user.name,
      },
    });
  } catch (error) {
    // Log failed attempt
    await logFailedLogin(email, req.ip);

    res.status(401).json({ error: 'Invalid credentials' });
  }
});

2. Input Sanitization Middleware

Comprehensive input validation for all API routes.

Global Validation Middleware:

// middleware/validation.js
import validator from 'validator';
import DOMPurify from 'dompurify';
import { JSDOM } from 'jsdom';

const { window } = new JSDOM('');
const DOMPurifyServer = DOMPurify(window);

export function validateAndSanitizeInput(input, rules) {
  const errors = [];
  const sanitized = {};

  for (const [field, rule] of Object.entries(rules)) {
    const value = input[field];

    // Required check
    if (rule.required && (value === undefined || value === null || value === '')) {
      errors.push(`${field} is required`);
      continue;
    }

    if (value === undefined || value === null) {
      continue;
    }

    let sanitizedValue = value;

    // Type validation and sanitization
    switch (rule.type) {
      case 'string':
        if (typeof value !== 'string') {
          errors.push(`${field} must be a string`);
          continue;
        }

        sanitizedValue = validator.escape(value);

        if (rule.maxLength && value.length > rule.maxLength) {
          errors.push(`${field} must be less than ${rule.maxLength} characters`);
        }

        if (rule.minLength && value.length < rule.minLength) {
          errors.push(`${field} must be at least ${rule.minLength} characters`);
        }

        if (rule.pattern && !rule.pattern.test(value)) {
          errors.push(`${field} format is invalid`);
        }
        break;

      case 'email':
        if (!validator.isEmail(value)) {
          errors.push(`${field} must be a valid email address`);
        }
        sanitizedValue = validator.normalizeEmail(value);
        break;

      case 'url':
        if (!validator.isURL(value, { protocols: ['http', 'https'] })) {
          errors.push(`${field} must be a valid URL`);
        }
        sanitizedValue = validator.escape(value);
        break;

      case 'html':
        sanitizedValue = DOMPurifyServer.sanitize(value, {
          ALLOWED_TAGS: rule.allowedTags || [],
          ALLOWED_ATTR: rule.allowedAttr || [],
        });
        break;

      case 'number':
        const num = Number(value);
        if (isNaN(num)) {
          errors.push(`${field} must be a number`);
          continue;
        }

        if (rule.min !== undefined && num < rule.min) {
          errors.push(`${field} must be at least ${rule.min}`);
        }

        if (rule.max !== undefined && num > rule.max) {
          errors.push(`${field} must be at most ${rule.max}`);
        }

        sanitizedValue = num;
        break;

      case 'boolean':
        sanitizedValue = Boolean(value);
        break;

      case 'array':
        if (!Array.isArray(value)) {
          errors.push(`${field} must be an array`);
          continue;
        }

        if (rule.maxLength && value.length > rule.maxLength) {
          errors.push(`${field} must have at most ${rule.maxLength} items`);
        }

        // Sanitize array items if item rules are provided
        if (rule.itemRules) {
          sanitizedValue = value.map(item =>
            validateAndSanitizeInput({ item }, { item: rule.itemRules }).sanitized.item
          ).filter(item => item !== undefined);
        }
        break;
    }

    sanitized[field] = sanitizedValue;
  }

  return { sanitized, errors, isValid: errors.length === 0 };
}

Usage in API Routes:

// pages/api/contact.js
import { validateAndSanitizeInput } from '@/middleware/validation';

const contactRules = {
  name: { type: 'string', required: true, minLength: 2, maxLength: 100 },
  email: { type: 'email', required: true },
  message: { type: 'string', required: true, minLength: 10, maxLength: 1000 },
  website: { type: 'url', required: false },
};

export default async function handler(req, res) {
  if (req.method !== 'POST') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  const { sanitized, errors, isValid } = validateAndSanitizeInput(req.body, contactRules);

  if (!isValid) {
    return res.status(400).json({ errors });
  }

  // Process sanitized data
  try {
    await sendContactEmail(sanitized);
    res.status(200).json({ success: true });
  } catch (error) {
    console.error('Contact form error:', error);
    res.status(500).json({ error: 'Internal server error' });
  }
}

3. Secure Headers Configuration

Comprehensive security headers for Next.js applications.

next.config.js Security Headers:

// next.config.js
module.exports = {
  async headers() {
    return [
      {
        source: '/(.*)',
        headers: [
          // Prevent clickjacking
          {
            key: 'X-Frame-Options',
            value: 'DENY',
          },
          // Prevent MIME type sniffing
          {
            key: 'X-Content-Type-Options',
            value: 'nosniff',
          },
          // Referrer policy
          {
            key: 'Referrer-Policy',
            value: 'strict-origin-when-cross-origin',
          },
          // Prevent XSS
          {
            key: 'X-XSS-Protection',
            value: '1; mode=block',
          },
          // Force HTTPS
          {
            key: 'Strict-Transport-Security',
            value: 'max-age=63072000; includeSubDomains; preload',
          },
          // Content Security Policy
          {
            key: 'Content-Security-Policy',
            value: [
              "default-src 'self'",
              "script-src 'self' 'unsafe-inline' 'unsafe-eval'",
              "style-src 'self' 'unsafe-inline'",
              "img-src 'self' data: https:",
              "font-src 'self'",
              "connect-src 'self'",
              "media-src 'self'",
              "object-src 'none'",
              "frame-src 'none'",
              "base-uri 'self'",
              "form-action 'self'",
              "frame-ancestors 'none'",
            ].join('; '),
          },
          // Permissions policy
          {
            key: 'Permissions-Policy',
            value: 'camera=(), microphone=(), geolocation=(), payment=()',
          },
        ],
      },
      // API routes - more restrictive
      {
        source: '/api/(.*)',
        headers: [
          {
            key: 'X-Frame-Options',
            value: 'DENY',
          },
          {
            key: 'Content-Security-Policy',
            value: "default-src 'none'",
          },
        ],
      },
    ];
  },

  // Additional security settings
  poweredByHeader: false,
  compress: true,
  reactStrictMode: true,
};

4. Database Security Best Practices

Secure database connections and queries in Next.js.

Secure Database Configuration:

// lib/db.js
import { Pool } from 'pg';
import mysql from 'mysql2/promise';

const isProduction = process.env.NODE_ENV === 'production';

// PostgreSQL configuration
const pgPool = isProduction ? new Pool({
  connectionString: process.env.DATABASE_URL,
  ssl: {
    rejectUnauthorized: true,
  },
  max: 10, // Maximum connections
  idleTimeoutMillis: 30000,
  connectionTimeoutMillis: 2000,
}) : new Pool({
  connectionString: process.env.DATABASE_URL,
});

// MySQL configuration
const mysqlPool = isProduction ? mysql.createPool({
  uri: process.env.DATABASE_URL,
  ssl: {
    rejectUnauthorized: true,
  },
  connectionLimit: 10,
  acquireTimeout: 60000,
  timeout: 60000,
}) : mysql.createPool({
  uri: process.env.DATABASE_URL,
});

export { pgPool, mysqlPool };

Secure Query Builder:

// lib/secure-query.js
import sql from 'sql-template-tag';

export function buildUserQuery(filters) {
  const conditions = [];
  const values = [];

  if (filters.name) {
    conditions.push('name ILIKE $' + (values.length + 1));
    values.push(`%${filters.name}%`);
  }

  if (filters.email) {
    conditions.push('email = $' + (values.length + 1));
    values.push(filters.email);
  }

  if (filters.age && typeof filters.age === 'number') {
    conditions.push('age >= $' + (values.length + 1));
    values.push(filters.age);
  }

  if (filters.status && ['active', 'inactive'].includes(filters.status)) {
    conditions.push('status = $' + (values.length + 1));
    values.push(filters.status);
  }

  const whereClause = conditions.length > 0 ? `WHERE ${conditions.join(' AND ')}` : '';

  return sql`
    SELECT id, name, email, age, status, created_at
    FROM users
    ${whereClause}
    ORDER BY created_at DESC
    LIMIT 100
  `;
}

5. Error Handling and Logging

Secure error handling to prevent information leakage.

Global Error Handler:

// pages/_error.js
import Error from 'next/error';

function MyError({ statusCode, hasGetInitialPropsRun, err }) {
  // Log error securely
  if (err) {
    console.error('Application error:', {
      message: err.message,
      stack: process.env.NODE_ENV === 'development' ? err.stack : undefined,
      statusCode,
      url: typeof window !== 'undefined' ? window.location.href : undefined,
    });
  }

  return (
    <div style={{ padding: '20px', textAlign: 'center' }}>
      <h1>{statusCode ? `Error ${statusCode}` : 'An error occurred'}</h1>
      <p>
        {statusCode === 404
          ? 'The page you are looking for was not found.'
          : 'Something went wrong. Please try again later.'}
      </p>
      <button onClick={() => window.location.reload()}>
        Reload Page
      </button>
    </div>
  );
}

MyError.getInitialProps = ({ res, err, asPath }) => {
  const statusCode = res ? res.statusCode : err ? err.statusCode : 404;

  // Log error details server-side
  if (err) {
    console.error('Server error:', {
      message: err.message,
      stack: err.stack,
      statusCode,
      path: asPath,
    });
  }

  return { statusCode };
};

export default MyError;

Security Monitoring Setup:

// lib/security-monitor.js
class SecurityMonitor {
  static async logSecurityEvent(event, details) {
    const logEntry = {
      timestamp: new Date().toISOString(),
      event,
      details,
      ip: this.getClientIP(),
      userAgent: typeof window !== 'undefined' ? window.navigator.userAgent : 'server',
      url: typeof window !== 'undefined' ? window.location.href : 'server',
    };

    // Store in database or send to monitoring service
    try {
      await fetch('/api/security/log', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(logEntry),
      });
    } catch (error) {
      console.error('Failed to log security event:', error);
    }

    // Also log to console in development
    if (process.env.NODE_ENV === 'development') {
      console.warn('Security Event:', logEntry);
    }
  }

  static getClientIP() {
    // Implementation depends on hosting provider
    // For Vercel: req.headers['x-forwarded-for']
    // For Netlify: req.headers['x-nf-client-connection-ip']
    return 'unknown';
  }

  static logFailedAuth(credentials, ip) {
    this.logSecurityEvent('FAILED_AUTH', {
      username: credentials.username || credentials.email,
      ip,
    });
  }

  static logSuspiciousActivity(activity, details) {
    this.logSecurityEvent('SUSPICIOUS_ACTIVITY', {
      activity,
      details,
    });
  }
}

export default SecurityMonitor;

Next.js Security Checklist 2025

API Routes: Validate all inputs, use parameterized queries
Middleware: Implement proper authentication and authorization
SSR Security: Sanitize getServerSideProps and getStaticProps inputs
Image Security: Configure domains and validation for Next.js Image
Environment Variables: Never expose secrets to client-side code
Rate Limiting: Implement rate limiting on sensitive endpoints
Headers: Configure comprehensive security headers
Error Handling: Prevent information leakage in error messages
Database Security: Use parameterized queries and connection pooling
Dependencies: Regularly audit and update npm packages
Logging: Implement security event logging and monitoring
Input Validation: Validate and sanitize all user inputs
Authentication: Implement secure session management
File Uploads: Validate file types, sizes, and contents
CORS: Configure Cross-Origin Resource Sharing properly

Conclusion

Next.js security requires understanding both general web security principles and Next.js-specific attack vectors. The framework's powerful features like SSR, API routes, and middleware introduce unique security considerations that must be addressed proactively.

Key takeaways for 2025:

API routes are prime targets for injection attacks
SSR functions can be exploited through malicious input
Middleware authentication can be bypassed without proper validation
Environment variables must never be exposed to client-side code
Image optimization features can enable SSRF attacks

By implementing comprehensive input validation, secure authentication, proper error handling, and regular security audits, you can build robust, secure Next.js applications that protect both your users and your business from evolving security threats.

Stay vigilant, keep dependencies updated, and implement defense in depth to maintain a strong security posture in your Next.js applications.

Next.js Security Vulnerabilities and Attack Vectors 2025

Table of Contents

Next.js Security Vulnerabilities and Attack Vectors 2025

Next.js Security Landscape 2025

Next.js-Specific Attack Vectors

Advanced Next.js Security Patterns

Next.js Security Checklist 2025

Conclusion

Rafael De Paz

React Security Vulnerabilities and Best Practices 2025

Understanding Next.js Security Best Practices and Common Vulnerabilities

Modern Authentication Patterns: JWT, OAuth, and Beyond

Building a Personal Blog with Next.js and Markdown