Linux Kernel EUVD-2026-32486

Upgrade to a patched Linux kernel: 6.6.140 or later on the 6.6 LTS branch, 6.12.86 or later on the 6.12 branch, 6.18.27 or later on the 6.18 branch, or 7.0.4 (also 7.1-rc1) on mainline. Upstream fix commits are available at git.kernel.org stable trees including https://git.kernel.org/stable/c/c0d3ccc6929e4509076df8f30a4fb1dc5018b0ae and related commits. If kernel upgrade is not immediately feasible, removing the ucan module (modprobe -r ucan) on systems that do not use UCAN USB-to-CAN hardware eliminates all exposure with zero operational impact. On systems that do require UCAN hardware, physically disconnecting and reconnecting the USB adapter instead of performing software-driven unbind operations prevents the leak path until a patched kernel is deployed; however, this is not always operationally practical in embedded or industrial environments. Distribution-specific kernel package updates from the vendor should be checked independently, as downstream packaging schedules vary.