CVE-2026-74679

A flaw was found in the Linux kernel's USB gadget NCM (Network Control Model) function (f_ncm). A malicious host can exploit an integer overflow vulnerability by supplying a large offset. This overflow causes a signed index variable to become negative, bypassing security checks and leading to an out-of-bounds read. This could result in information disclosure from kernel memory.

This vulnerability is rated as Moderate impact for Red Hat products because triggering the issue requires specific hardware and software configurations operating in USB gadget (device) mode rather than standard host mode. A connected malicious USB host can induce an out-of-bounds kernel memory read to cause a system crash or disclose sensitive kernel data, but cannot achieve remote code execution across network boundaries. Standard enterprise deployments operate exclusively as USB hosts and do not enable or configure gadget network functions by default, leaving typical installations unaffected.

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.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.