CVE-2022-49550 is a vulnerability identified in the Linux kernel's ntfs3 filesystem driver. The issue arises because the ntfs3 driver lacks an implementation of the 'invalidate_folio' method, which is responsible for properly freeing cached data pages (folios) when they are no longer needed. Specifically, when data is written to an ntfs3 filesystem and the filesystem is subsequently unmounted, the cached written data is not freed, resulting in a memory leak. This leak occurs because the kernel's page cache retains these folios indefinitely due to the missing invalidation mechanism. Over time, especially on systems with frequent mount/unmount cycles or heavy write operations to ntfs3 filesystems, this can lead to increased memory consumption, potentially exhausting system memory resources. The vulnerability does not appear to allow direct code execution or privilege escalation but impacts system stability and resource availability. The issue has been resolved by adding the 'block_invalidate_folio' method to the ntfs3 driver, ensuring that cached data is properly invalidated and freed upon unmounting. There are no known exploits in the wild, and no CVSS score has been assigned yet. The vulnerability affects Linux kernel versions containing the specified commit hashes prior to the patch. This is primarily a resource management flaw rather than a security bypass or data corruption vulnerability.

For European organizations, the primary impact of CVE-2022-49550 is related to system reliability and availability. Organizations running Linux systems with ntfs3 filesystem support—commonly used for interoperability with Windows-formatted NTFS drives—may experience gradual memory exhaustion if they frequently mount and unmount NTFS volumes or perform heavy write operations. This can lead to degraded system performance, potential crashes, or forced reboots, impacting critical services or applications relying on these systems. While the vulnerability does not directly compromise confidentiality or integrity, the availability impact can disrupt business operations, especially in environments where Linux servers or workstations handle external NTFS storage devices. This is particularly relevant for sectors with high data interchange between Windows and Linux systems, such as media production, research institutions, or cross-platform development environments. The lack of known exploits reduces immediate risk, but unpatched systems remain vulnerable to stability issues. Organizations with automated or embedded Linux systems that use ntfs3 for external storage should be cautious, as memory leaks can accumulate unnoticed and cause failures over time.

To mitigate CVE-2022-49550, European organizations should prioritize updating their Linux kernels to versions that include the patch adding the 'block_invalidate_folio' method to the ntfs3 driver. Kernel updates should be tested and deployed promptly, especially on systems that frequently interact with NTFS filesystems. For environments where immediate kernel upgrades are not feasible, organizations can minimize risk by reducing the frequency of mounting and unmounting NTFS volumes or limiting write operations to these filesystems. Monitoring system memory usage and setting up alerts for unusual memory consumption can help detect potential leaks early. Additionally, organizations should audit their use of ntfs3 and consider alternative filesystems or protocols for cross-platform file sharing where possible. Incorporating this vulnerability into routine patch management and vulnerability scanning processes will ensure timely detection and remediation. Finally, educating system administrators about this issue will help maintain awareness and encourage proactive system maintenance.