Nested Overlay Filesystem Vulnerability in Linux Kernel

CVE-2026-89768

What is CVE-2026-89768?

A flaw in the Linux kernel's handling of path mappings for nested overlay filesystems has been identified, where the user-visible path of backing files is incorrectly derived. This issue arises when one backing file is nested within another, causing the real user path to be obscured in system diagnostics such as /proc//maps and perf/ftrace records. The vulnerability can lead to discrepancies in file path visibility, making it challenging for users and processes to accurately access files, thereby potentially disrupting file management operations in complex storage architectures.

References