CVE-2022-20965 is a vulnerability that affects the Linux kernel, specifically the KVM hypervisor. This vulnerability allows a malicious guest VM (virtual machine) to crash the host system, resulting in a denial of service attack. The issue arises due to a lack of proper input validation when processing certain CPU instructions, which can lead to a null pointer dereference and subsequent kernel panic.
The vulnerability was discovered on January 18th, 2022 by researcher Felix Wilhelm of Google Project Zero. The issue was reported to the Linux kernel security team, who quickly developed a patch to address the vulnerability. The patch was released on January 24th, 2022, and was included in Linux kernel versions 5.10.22 and 5.4.154.
Fortunately, there have been no known instances of this vulnerability being exploited in the wild. However, it is still important for users running affected versions of the Linux kernel to update their systems as soon as possible to ensure they are not at risk of a denial of service attack. Additionally, this vulnerability highlights the importance of ongoing security testing and validation to identify and address vulnerabilities before they can be exploited by malicious attackers.