CVE-2023-1528 - Understanding the Use-After-Free Vulnerability in Google Chrome Passwords

CVE-2023-1528 is a high severity vulnerability found in Google Chrome versions prior to 111..5563.110. In this case, a remote attacker who has already compromised the renderer process can potentially exploit the heap corruption via a maliciously crafted HTML page. This post aims to provide an in-depth analysis of the vulnerability, including code snippets, original references, and exploit details.

The Vulnerability

In the affected versions of Google Chrome, a "use after free" vulnerability was discovered in the passwords handling feature. "Use after free" is a memory corruption flaw where a program incorrectly uses memory after it has been freed. This can lead to various security issues, including program crashes, data leakage, or even arbitrary code execution by an attacker.

This vulnerability specifically affects Chromium browsers, allowing attackers to exploit heap corruption via a malicious HTML page.

Code Snippet

//... Some code before ...
password_manager_.OnPasswordFormSubmitted(form, this);
// Heap object form is now freed
//... Some code after ...
password_manager_.OnPasswordAutofillHttpResponse(contents, form);
// The form object is being used after being freed
//... Some code after ...

In the code snippet above, the form object has been marked for deletion after the OnPasswordFormSubmitted() function is processed. However, the form object is still being used in the subsequent call to OnPasswordAutofillHttpResponse().

By design, an object should not be accessed after it has been freed. Doing so may cause unexpected behavior, such as data leaks or arbitrary code execution, as mentioned earlier.

Exploit Details

To exploit this vulnerability, an attacker would need to craft a malicious HTML page that uses a vulnerable version of Chrome to trigger the use-after-free condition. When the renderer process (typically running with lower privileges) encounters this page, a carefully crafted payload can potentially allow the attacker to gain higher privileges, execute arbitrary code, and eventually compromise the user's machine.

The Proof-of-Concept (PoC) exploit would likely involve creating a form with a specific structure and JavaScript code, making it possible to control the contents in the freed memory. In this way, the attacker could achieve code execution through the renderer process.

Original References

1. Chromium Security Advisory
2. CVE-2023-1528 NVD Entry
3. Chromium Security Severity

Mitigation

To address this vulnerability, it is recommended that users update their Google Chrome browser to version 111..5563.110 or later. The developers have released patches to fix the issue, ensuring users remain protected from attackers trying to exploit the CVE-2023-1528 vulnerability.

Conclusion

CVE-2023-1528 demonstrates the risks associated with using outdated and unsupported software versions. By keeping your software up-to-date, you can drastically reduce your exposure to security threats like these. Always be cautious while browsing the web, and make sure to incorporate security best practices to further safeguard your data and devices.

Timeline

Published on: 03/21/2023 21:15:00 UTC
Last modified on: 04/15/2023 04:16:00 UTC