CVE-2025-1426 - Heap Buffer Overflow in GPU on Google Chrome for Android Explained

CVE-2025-1426 is a recently disclosed security vulnerability found in the GPU component of Google Chrome for Android. It affects Chrome versions earlier than 133..6943.126. This bug lets a remote attacker exploit heap corruption by convincing a user to visit a specially crafted HTML page. Google classified this as a High severity security issue.


> TL;DR:
> If you’re using Chrome on Android and it’s not updated to version 133..6943.126 or later, you’re at risk of getting hacked just by visiting a malicious website.

Technical Background

A heap buffer overflow occurs when a program writes more data to a block of memory (the heap) than it was allocated. In the context of a browser, heap overflows in the GPU process can let bad actors execute code, crash the browser, or escalate privileges.

In Chrome, the GPU process deals with all rendering and graphic output. If an attacker can corrupt memory here (using HTML and JavaScript), it opens up powerful exploitation possibilities due to the low-level nature of graphics operations.

How Could This Be Exploited?

Imagine a malicious website. If you visit, it feeds the Chrome GPU code with data designed to overflow the intended buffer. The GPU process, tricked by the data, might end up overwriting adjacent parts of its memory. This could allow the attacker to:

Real-World Example

Here's a simplified hypothetical illustration using JavaScript and WebGL (as these attack surface the GPU):

<!-- Malicious HTML using WebGL -->
<canvas id="webgl-canvas"></canvas>
<script>
  // Flood the GPU with lots of large textures or malformed data
  const gl = document.getElementById('webgl-canvas').getContext('webgl');
  for (let i = ; i < 10000; i++) {
    let tex = gl.createTexture();
    gl.bindTexture(gl.TEXTURE_2D, tex);
    // Overly large or invalid texture size/format triggers a buffer overflow internally
    gl.texImage2D(gl.TEXTURE_2D, , gl.RGBA, 99999, 99999, , gl.RGBA, gl.UNSIGNED_BYTE, null);
  }
</script>

> Note: The snippet above might not trigger the actual bug, but shows how attackers abuse the GPU interface (like WebGL) via confusing/malicious page code.

References and Further Details

- Chromium Release Notes (Versions 133..6943.126)
- Chromium Security Advisories
- CVE Record for CVE-2025-1426

Google swiftly patched this vulnerability and released the update in Chrome 133..6943.126. They advise users to update immediately.

How is This Exploited?

The attacker would create a webpage that uses the GPU (like via WebGL, Canvas, or certain CSS operations) with weird or huge data that the bug mishandles. When a vulnerable Chrome loads the page, this causes a buffer overflow. If successfully exploited, the attacker may execute code with the permissions of Chrome—dangerous on a personal device.

Proof of Concept (PoC):
Google and security researchers typically don’t publish full working exploits directly, but bug trackers sometimes discuss details. For example, security researchers may fuzz WebGL or related APIs for Chrome, sending malformed requests until Chrome’s GPU process crashes. The attacker would analyze such crashes, then write an HTML+JavaScript exploit tailored to trigger the specific heap overflow.

Final Thoughts

Heap buffer overflows are notoriously dangerous, especially in complex software like browsers. They can lead to total software compromise. With CVE-2025-1426, simply *visiting* a bad page was enough to risk your security.

Links

- Download latest Chrome for Android
- Official Google Chrome Security Blog

*This article is for educational and awareness purposes only. Don’t try to exploit this vulnerability. Report any suspicious activity to your browser or device provider.*

Timeline

Published on: 02/19/2025 17:15:15 UTC
Last modified on: 02/19/2025 20:15:36 UTC