Google Chrome is one of the most used web browsers across the world, and as such, it is essential to ensure the security of its users. A use after free vulnerability in WebRTC in Google Chrome has been identified, named CVE-2023-0932, which affects Windows systems prior to version 110..5481.177. This vulnerability could potentially allow remote attackers to exploit heap corruption via a crafted HTML page, if a user engages in specific UI interactions as prompted by the attacker. Due to the potential severity of this vulnerability, the Chromium security team has classified the severity as "High".

In this post, we will be examining the details of CVE-2023-0932, including code snippets and original references, as well as discussing how to exploit the vulnerability and potential mitigation strategies.

Vulnerability Description

The CVE-2023-0932 vulnerability relates to a use after free issue in WebRTC in Google Chrome on Windows. This vulnerability is caused by improper handling of certain objects, leading to a use after free condition. When the freed object is later accessed, this could lead to potential heap corruption and allow hackers to execute arbitrary code on the affected system.

A remote attacker successfully convinces a user to visit a maliciously crafted webpage.

2. The attacker prompts the victim to engage in specific UI interactions that trigger the vulnerability.
3. As a result of these interactions, heap corruption can occur, allowing the attacker to potentially execute arbitrary code on the victim's system.

Code Snippet

The vulnerability is present in WebRTC of Google Chrome, and while the exact code lines that provoke the vulnerability have not been disclosed to prevent potential exploitation, a general understanding of the issue can be gained from the following code snippet:

...
/* function that causes use after free in WebRTC */
void VulnerableFunction() {
  scoped_refptr<rtc::RefCountedObject> ref_obj = new rtc::RefCountedObject();
  ...
  ref_obj->SomeOperation();
  ...
  ref_obj = nullptr;
  ...
  // Use after free occurs here
  ref_obj->AnotherOperation();
  ...
}
...

As seen in the code snippet, an object is created with a reference count, the object is used for some operation, the reference count is set to nullptr, and then the object is accessed again, causing a use after free.

Exploiting this vulnerability requires

1. Crafting a malicious webpage with HTML and JavaScript code that leverages the affected WebRTC functionality.
2. Successfully convincing a victim to visit the webpage and engage in specific UI interactions to trigger the vulnerability.

Update Google Chrome on Windows to version 110..5481.177 or later.

2. Employ security best practices, such as not visiting unknown websites or engaging in suspicious UI interactions.
3. Utilize security tools, such as antivirus software and firewalls, to detect and block potential threats.

Original References

1. Chromium Security Advisory
2. CVE-2023-0932 - NVD Detail
3. Google Chrome Security Blog

Conclusion

The exploitation of CVE-2023-0932 can have severe consequences for affected users, ranging from privacy breaches to potential loss of data. Hence, it is of the utmost importance to prioritize the security of the users by continuously updating the software to the latest available versions and ensuring that robust security measures are in place.

Timeline

Published on: 02/22/2023 20:15:00 UTC
Last modified on: 02/28/2023 02:19:00 UTC