Linux Kernel CVE-2026-43319

Upgrade to patched Linux kernel versions: 6.12.75 or later for 6.12.x branch, 6.18.16 or later for 6.18.x branch, 6.19.6 or later for 6.19.x branch, or 7.0 stable release for mainline deployments. Patch commits are available from kernel.org stable tree (links: https://git.kernel.org/stable/c/e341e18215030af2136836b78508e0d798916df7, https://git.kernel.org/stable/c/f8431b8672231d378b03176fe74c95adfd3522cf, https://git.kernel.org/stable/c/40534d19ed2afb880ecf202dab26a8e7a5808d16, https://git.kernel.org/stable/c/41ccfac7d302968a4f32b5f7b012d066c5f5cdf8). For systems where immediate kernel upgrade is not feasible, implement compensating controls: restrict access to /dev/spidev* device nodes to only essential system services via udev rules (limiting group membership reduces attack surface but does not eliminate risk from already-privileged processes); audit and refactor applications accessing SPI devices to use single-threaded access patterns or application-level locking around spidev file descriptor operations (introduces application complexity and potential performance impact); or disable spidev module entirely if userspace SPI access is not required (breaks functionality for applications depending on spidev interface). Note that restricting device node permissions only reduces exposure-it does not prevent exploitation by already-authorized processes, so patching remains the definitive mitigation.