CVE-2026-64059

A flaw was found in the Linux kernel's network filesystem (netfs) component. The netfs_perform_write() function, responsible for handling write operations, does not correctly manage private data associated with memory pages, known as folios. This improper handling can lead to memory leaks, where system resources are not properly released. Such leaks could potentially be exploited by an attacker to cause a denial of service by exhausting available memory or to gain unauthorized access to sensitive information.

Red Hat has evaluated this issue as having a Moderate security impact because successful exploitation requires local user privileges to perform write operations on an active network filesystem mount utilizing the netfs library. The vulnerability stems from improper tracking of memory folio state during buffered write operations, resulting in reference leaks and gradual memory exhaustion. Because the flaw cannot be triggered remotely without local write permissions and does not facilitate privilege escalation or arbitrary code execution, the overall risk is limited.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.