Linux Kernel EUVD-2026-27804

Upgrade to patched Linux kernel versions appropriate for your kernel branch: 5.10.252 or later for 5.10.x series, 5.15.202+ for 5.15.x, 6.1.165+ for 6.1.x, 6.6.128+ for 6.6.x, 6.12.75+ for 6.12.x, 6.18.16+ for 6.18.x, 6.19.6+ for 6.19.x, or upgrade to mainline kernel 7.0 or later. Patches available from kernel.org stable trees (https://git.kernel.org/stable/) with specific commits identified in references. For systems unable to immediately patch, implement compensating controls: unload the ntb_hw_switchtec kernel module if NTB functionality is not required (modprobe -r ntb_hw_switchtec), configure NTB with fewer than MAX_MWS memory windows if operationally feasible, or restrict local user access to systems with Switchtec hardware through stricter authentication policies and user privilege reduction. Note that disabling the driver eliminates NTB functionality entirely, impacting inter-system memory access for clustered applications. Validate NTB configuration post-patching to ensure memory window settings remain within supported bounds. Systems without Switchtec hardware can deprioritize this update in favor of higher-risk vulnerabilities.