Google Chrome is the world’s most popular browser, and its Web Payments API powers fast transactions on millions of devices. But hidden in the complex code are sometimes serious threats. One such threat, CVE-2023-0927, was discovered affecting Chrome on Android – and it demonstrates why browser security matters for everyday users.

Let’s break down what CVE-2023-0927 is, see how it was exploited, and understand why it’s so dangerous – using simple, clear language, along with example code and links for deeper reading.

What is CVE-2023-0927?

CVE-2023-0927 is a high-severity vulnerability found in Google Chrome for Android, specifically prior to version 110..5481.177. The bug is classified as a “use-after-free” in the Web Payments API – a specialized API that lets sites request payments from users, integrating with native payment apps on Android.

In plain terms:  
A “use-after-free” happens when a program frees (deletes) a chunk of memory but then continues to use it. This is a big danger! It can let attackers run their own code, crash your browser, or steal sensitive data.

Official advisory:  
- Google Chrome Release Notes  
- NVD Database Entry  
- Chromium Issue Tracker *(may require login for full details)*

Where Did the Problem Happen?

The bug was found in Chrome’s implementation of the *Web Payments API* on Android, specifically in how it handled certain lifecycle events. Attackers who had already compromised the renderer process (meaning: they controlled some code that runs inside a web page) could interact with the API in a way that confused Chrome into using disconnected, and already-freed, objects.

Here’s a toy example, simplified to explain the problem

// Don't worry if you don't read C++!
// Think of "free()" as "delete this thing".
Object* ptr = new Object();   // allocate new object

delete ptr;                   // free memory

ptr->doSomething();           // using memory after it's deleted – BAD!

In browser engines, *just like the code above*, this mistake could let an attacker get control over what’s in “ptr”, potentially leading to code execution or crash.

Exploiting CVE-2023-0927: What’s the Attack?

Attackers couldn’t just visit any web page to hit this bug. Instead, they had to do something more advanced, like exploiting another bug first to gain some code running inside the Chrome renderer process (like a sandbox escape or XSS). Then, they would use a carefully crafted HTML/JavaScript page to:

Cause Chrome to access that now-freed object, which they partially controlled,

4. This could corrupt the “heap memory” (the part of memory used for dynamic allocation), which sometimes can let attackers run their own code.

A plausible JavaScript attack flow (simplified)

// attacker.js
let req = new PaymentRequest(/* ...payment details... */);

req.show().then(function(paymentResponse) {
    // In the handler, do something to confuse the API, like:
    // - Detach frame, or
    // - Delete underlying objects, or
    // - Repeated calls to .abort()
    document.body.innerHTML = ''; // Simulate removal of page/frame

    // Now, further actions (by accident or design) may use the freed object
});

*This is just a stylized example for illustration; actual exploits are more complex and rely on how Chrome manages these objects internally.*

Why Is This Bad?

A successful “use-after-free” can be extremely dangerous in Chrome, especially on Android, where browsers have more privileges and often less isolation.

- Heap Corruption: Attackers may overwrite part of browser memory, allowing them to steer what code runs next.
- Full Remote Exploit: If chained with other bugs, this could allow remote code execution or escape the Chrome sandbox.

Google themselves rated this as High severity.

How Was It Fixed?

Google patched the vulnerability in Chrome 110..5481.177 for Android. The fix ensures that the browser handles object lifecycles in the Web Payments API more safely and doesn’t access already-freed memory.

Upgrade Advice:  
If you’re using Chrome on Android, make sure you’re running *at least* version 110..5481.177 or newer.

- CVE-2023-0927 on NVD
- Chromium Security Release Notes 110..5481.177
- Chromium Bug 1413734 (may require sign-in)

Final Thoughts

CVE-2023-0927 is another reminder that even small mistakes in browser code can put millions at risk, especially on mobile where browsers interact with sensitive services like payments. While remote code execution through chains including this bug is rare for everyday users, it shows why constant browser updates are absolutely essential.

Stay safe, and always surf with up-to-date software!

*(This post is exclusive content, written for easy understanding. It summarizes public details but does not contain or endorse weaponized exploit code.)*

Timeline

Published on: 02/22/2023 20:15:00 UTC
Last modified on: 03/03/2023 04:43:00 UTC