CVE-2026-64121

A flaw was found in the Linux kernel's Intermediate Functional Block (ifb) network device. A local user with network configuration privileges can trigger a slab-out-of-bounds read by configuring an asymmetric ifb device and querying its ethtool statistics. This vulnerability can lead to a kernel crash, resulting in a denial of service, and potentially disclose sensitive information by reading adjacent memory data.

This vulnerability is rated as having Moderate impact because exploitation requires local privileges to create an asymmetric virtual network interface or inspect its ethtool statistics, restricting the failure domain to a local kernel crash or reading adjacent kernel memory. The Intermediate Functional Block (ifb) kernel module is not loaded by default in standard Red Hat Enterprise Linux deployments and is typically utilized only in specialized network traffic shaping scenarios. Consequently, standard installations that do not configure IFB interfaces remain unexposed to this condition during normal operations.

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.