A recently discovered critical vulnerability, dubbed CVE-2022-21814, has been identified in the NVIDIA GPU Display Driver for Linux. This vulnerability is caused by improper handling of insufficient permissions or privileges and can allow an unprivileged local user to gain limited write access to protected memory. In turn, this can lead to denial of service (DoS).

In this long read, we will delve into the details of the exploit, offer insights into the code snippet associated with the vulnerability, and provide links to crucial original references.

Vulnerability Details

CVE-2022-21814 affects NVIDIA GPU Display Driver for Linux, specifically the kernel driver package. The vulnerability exists due to improper handling of insufficient permissions or privileges. An unprivileged local user can exploit this vulnerability to gain limited write access to protected memory. This access can result in denial of service (DoS), effectively rendering the affected systems and services unusable.

Code Snippet

Although the actual vulnerable code snippet cannot be shared due to proprietary concerns, a pseudo-code representation of the issue can be provided to give a glimpse into the problem.

// Vulnerable NVIDIA Kernel Driver pseudo-code

int affected_function(struct some_arguments args) {
    ...
    if (!privileged_user(args.user)) {
        return PERMISSION_DENIED;
    }

    some_call_that_is_vulnerable(args);

    ...
}

int some_call_that_is_vulnerable(struct some_arguments args) {
    ...
    // Improper handling of permissions or privileges
    if (!privileged_user(args.user)) {
        // Limited write access to protected memory
        ... 
    }
    ...
}

As seen in the pseudo-code, the function some_call_that_is_vulnerable does not handle permissions or privileges correctly, leading to an unprivileged local user gaining limited write access to protected memory.

1. Official NVIDIA Security Bulletin: NVIDIA has released an official Security Bulletin containing details and mitigation steps for the vulnerability.
2. NVD - CVE-2022-21814: The National Vulnerability Database has documented the vulnerability's details, including its CVSS score, impact, and affected versions.

Exploit Details

At the time of writing this post, there are no known public exploits of CVE-2022-21814. However, the vulnerability's severity, coupled with its potential impact, warrants prompt attention and patching.

Mitigation

To prevent exploitation of this vulnerability, NVIDIA has advised users to update their GPU Display Driver for Linux to the latest available version. Patched driver versions include:

R465 branch: 465.33.02

Updating the NVIDIA GPU Display Driver for Linux is a simple process that varies depending on your Linux distribution and can be done via package manager or manual installation.

Conclusion

CVE-2022-21814 is a critical vulnerability in the NVIDIA GPU Display Driver for Linux that can lead to denial of service for affected systems. Users are encouraged to update their systems with the latest available driver as soon as possible.

Remember to stay vigilant about maintaining your systems to minimize the risk of security breaches. Regularly check for updates and apply patches, not only for NVIDIA GPU Display Driver but also for all software running on your devices. This will help keep your systems secure and functioning optimally.

Timeline

Published on: 02/07/2022 20:15:00 UTC
Last modified on: 05/09/2022 20:15:00 UTC