Clickjacking in Fiber with Jwt Tokens

Clickjacking is a client-side vulnerability where an attacker tricks a user into clicking or interacting with a transparent or disguised UI element inside an iframe. When a web application uses Jwt Tokens for authentication but does not enforce protections against embedding, an attacker can host a malicious page that loads the target site in an invisible iframe. If the victim is authenticated with a valid Jwt Token stored in a cookie or in browser storage, any state-changing request initiated by the attacker (e.g., a form POST or a fetch with the Jwt Token) may execute with the victim’s permissions.

In Fiber, if routes rely on Jwt Token validation via middleware but do not set appropriate HTTP headers to prevent framing, the application is exposed. For example, a protected route that validates a Jwt Token from the Authorization header can still be invoked via an iframe if the browser sends cookies automatically. Even when Jwt Tokens are used, browsers include credentials for same-site requests unless explicitly restricted. Without anti-clickjacking defenses such as X-Frame-Options or Content-Security-Policy frame-ancestors directives, an attacker can craft a page that overlays buttons or links on top of invisible content, causing unauthorized actions like changing email settings or initiating transactions.

The risk is especially pronounced when Jwt Tokens are stored in cookies without the SameSite attribute or when CORS rules are too permissive. A common pattern in Fiber applications is to validate Jwt Tokens in middleware and proceed to render protected UI; however, if the application serves responses with a default or missing Content-Security-Policy, an attacker’s site can load the target endpoint in a hidden iframe and use JavaScript to read or simulate user interactions. Because the scan tests unauthenticated attack surfaces, it can detect missing frame-protection headers and flag the exposed surface, even when Jwt Tokens are in use.

Remediation focuses on preventing your endpoints from being embedded while maintaining secure Jwt Token handling. You should set frame-protection headers and enforce strict CORS rules in Fiber middleware, independent of how Jwt Tokens are validated.

• Set X-Frame-Options: DENY or SAMEORIGIN to restrict framing.
• Use a strict Content-Security-Policy frame-ancestors directive.
• Ensure Jwt Tokens are transmitted securely via the Authorization header and avoid storing them in cookies unless necessary; if cookies are used, set HttpOnly, Secure, and SameSite=Strict or Lax.

Below are concrete Fiber code examples that combine secure Jwt Token validation with anti-clickjacking headers.

// main.go
package main

import (
	"github.com/gofiber/fiber/v2"
	"github.com/gofiber/fiber/v2/middleware/headers"
)

func main() {
	app := fiber.New()

	// Security headers to prevent clickjacking
	app.Use(headers.New(headers.Config{
		XContentTypeOptions: "nosniff",
		XFrameOptions:       "DENY",
		ContentSecurityPolicy: "default-src 'self'; frame-ancestors 'none';",
	}))

	// Jwt Token validation middleware
	app.Use(func(c *fiber.Ctx) error {
		auth := c.Get("Authorization")
		if len(auth) < 7 || auth[:7] != "Bearer " {
			return c.Status(fiber.StatusUnauthorized).SendString("Unauthorized")
		}
		token := auth[7:]
		// Validate token signature and claims here
		// For example, use jwt.Parse with your public key
		// If invalid, return Unauthorized
		return c.Next()
	})

	app.Get("/api/profile", func(c *fiber.Ctx) error {
		return c.JSON(fiber.Map{"profile": "protected data"})
	})

	app.Listen(":3000")
}

If you store Jwt Tokens in cookies (e.g., for browser-based clients), set cookie attributes strictly:

// Set secure cookie with anti-clickjacking context
app.Get("/login", func(c *fiber.Ctx) error {
	cookie := &fiber.Cookie{
		Name:     "access_token",
		Value:    "your-jwt-here",
		Expires:  time.Now().Add(24 * time.Hour),
		HTTPOnly: true,
		Secure:   true,
		SameSite: fiber.CookieSameSiteStrictMode,
	}
	c.Cookie(cookie)
	return c.SendString("Logged in")
})

These configurations ensure that even if a user is authenticated with a Jwt Token, the browser will not embed your app inside an attacker’s iframe, mitigating clickjacking while preserving token-based security.