Linux Kernel CVE-2026-43128

Apply vendor patches immediately for systems using RDMA hardware or InfiniBand: upgrade to Linux kernel 6.1.165+, 6.6.128+, 6.12.75+, 6.18.16+, 6.19.6+, or 7.0+ depending on your stable branch. Patch commits are available from git.kernel.org stable tree (links provided in references section). If immediate patching is not feasible, implement these compensating controls with noted trade-offs: (1) Disable RDMA user-space memory registration by setting kernel parameter 'rdma.disable_user_mem=1' - this breaks applications relying on InfiniBand verbs and RDMA-CM, including MPI libraries, Lustre clients, and NVMe-oF initiators; (2) Restrict access to /dev/infiniband/* device nodes to only essential service accounts via udev rules - reduces attack surface but does not prevent exploitation by compromised RDMA applications running as those accounts; (3) Deploy kernel memory corruption detection via CONFIG_KFENCE or CONFIG_KASAN on test systems to detect exploitation attempts - performance overhead makes this unsuitable for production. Verify patch application by checking kernel git commit hash matches the fixed versions listed in EUVD-2026-27691.