CVE-2022-24448 : Security Advisory and Response

An issue was discovered in fs/nfs/dir.c in the Linux kernel before 5.16.5. If an application sets the O_DIRECTORY flag and tries to open a regular file, nfs_atomic_open() performs a regular lookup. Instead of returning ENOTDIR as expected, the server returns uninitialized data in the file descriptor.

Understanding CVE-2022-24448

This CVE relates to a vulnerability in the Linux kernel before version 5.16.5 that allows uninitialized data to be returned in the file descriptor when the O_DIRECTORY flag is set.

What is CVE-2022-24448?

CVE-2022-24448 is a flaw in the Linux kernel's fs/nfs/dir.c that mishandles file openings, leading to the return of uninitialized data instead of an expected error code.

The Impact of CVE-2022-24448

This vulnerability could be exploited by a local attacker to obtain sensitive information or escalate privileges by leveraging the uninitialized data returned.

Technical Details of CVE-2022-24448

This section provides more in-depth technical information about the CVE.

Vulnerability Description

The issue arises from incorrect behavior in nfs_atomic_open() when processing file openings with the O_DIRECTORY flag, resulting in the return of uninitialized data.

Affected Systems and Versions

The vulnerability affects Linux kernel versions prior to 5.16.5. Systems using these versions may be vulnerable to the issue.

Exploitation Mechanism

Attackers can exploit this vulnerability by setting the O_DIRECTORY flag in an application and attempting to open a regular file, causing the server to return uninitialized data.

Mitigation and Prevention

To address CVE-2022-24448, follow the steps outlined below.

Immediate Steps to Take

Update to Linux kernel version 5.16.5 or later to mitigate the vulnerability.
Monitor official sources for patches and advisories related to this CVE.

Long-Term Security Practices

Ensure timely application of security updates to keep systems protected.
Employ principle of least privilege to limit potential damage from vulnerabilities.

Patching and Updates

Regularly check for security updates and patches from the Linux kernel maintainers to address CVE-2022-24448.