CVE-2026-43408 is a vulnerability in the Linux kernel's Ceph filesystem code where missing initializers for the ceph_path_info structure can cause kernel crashes. The issue arises because ceph_mdsc_build_path() must be called with a zero-initialized ceph_path_info parameter; otherwise, ceph_mdsc_free_path_info() may crash the kernel. This bug can lead to system instability and potentially privilege escalation.