In this long read post, we will explore a recently discovered vulnerability identified as CVE-2022-42803. This security issue affects a range of Apple operating systems, including tvOS, iOS, iPadOS, macOS, and watchOS. The vulnerability is characterized by a race condition that was addressed using improved locking mechanisms. When exploited, a malicious app may be able to execute arbitrary code with kernel privileges, leading to a significant security compromise.

Original References:

1. CVE-2022-42803
2. Apple Security Documentation

Vulnerability Details

The race condition vulnerability in the affected Apple operating systems results from improper locking mechanisms. The vulnerability can be exploited by a malicious app to execute arbitrary code with kernel privileges. This means that it could potentially gain complete control over the affected device, surpassing the access restrictions put in place by the operating system.

Code Snippet

The following code snippet demonstrates an example of a race condition vulnerability caused by improper locking:

// Main thread
lock();
read_data();
unlock();

// Worker thread
lock();
process_data();
unlock();

In this example, two threads attempt to access a shared resource. Assuming the lock and unlock functions work as intended, there should be no race condition since only one thread can access the resource at a time. However, if the lock implementation is flawed, both threads could access the shared resource simultaneously, leading to undesired behavior.

Exploit Details

To exploit this vulnerability, an attacker would need to create a malicious app that takes advantage of the flawed locking mechanism to inject and execute arbitrary code with kernel privileges. This could potentially grant the attacker full access to the victim's device, allowing them to exfiltrate data, install additional malicious software, or even perform a complete takeover of the device.

Users are advised to update their devices to the latest available versions of the affected Apple operating systems to protect against this vulnerability:

- Download iOS/iPadOS updates through Settings > General > Software Update

Update macOS via System Preferences > Software Update

- watchOS updates can be obtained through the Watch app on your iPhone, in the My Watch tab > General > Software Update

tvOS updates can be found in Settings > System > Software Updates > Update Software

The aforementioned updates contain the necessary patches and improvements to secure your devices against this CVE-2022-42803 vulnerability.

In conclusion, CVE-2022-42803 is a serious race condition vulnerability affecting numerous Apple operating systems. Users are encouraged to apply the updates provided by Apple as soon as possible to prevent the execution of malicious code with kernel privileges. Stay vigilant and maintain your devices updated to avoid potential security threats.

Timeline

Published on: 11/01/2022 20:15:00 UTC
Last modified on: 11/03/2022 03:53:00 UTC