CVE-2026-68124

A flaw was found in the Linux kernel's Message Control Transport Protocol (MCTP) serial driver. The driver's receive state machine incorrectly handles zero-length frames, leading to an out-of-bounds write. A local attacker with CAP_NET_ADMIN capabilities can exploit this vulnerability by sending specially crafted zero-length frames, which can result in arbitrary code execution or a denial of service.

This vulnerability poses minimal risk to Red Hat Enterprise Linux environments as the MCTP serial driver is not provided in standard kernel builds. Exploitation is substantially restricted by requiring local administrative privileges, specifically CAP_NET_ADMIN, to bind the line discipline and initialize the network interface. Consequently, unprivileged local users or remote actors cannot trigger the out-of-bounds write under standard deployment models.