CVE-2026-97564

A flaw was found in the Linux kernel's SMB (Server Message Block) client. This vulnerability allows a local user to achieve privilege escalation due to missing validation on identity mapping key descriptions. Because the kernel does not verify that identity mapping requests originate internally, a local attacker can supply arbitrary user and group attributes to be processed by a privileged helper utility running with root permissions.

This vulnerability is rated as Moderate impact for Red Hat Enterprise Linux because exploitation requires local authenticated access and relies on specific upcall configurations rather than exposing a remote attack vector. By default, the CIFS kernel module is not loaded on Red Hat platforms unless SMB shares are actively mounted. Although an unprivileged local user could potentially gain elevated privileges through crafted key descriptors processed by the user-mode helper, the dependency on active CIFS usage and local account access limits the severity.

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.