CVE-2026-98987

A flaw was found in the Linux kernel's mount namespace subsystem. A local user with mount privileges can trigger this issue during recursive mount operations when the topmost mount in a chain is a mount namespace file. Because the kernel fails to inspect the topmost mount in the chain, propagated mount copies are incorrectly attached to inaccessible internal locations. This improper attachment can result in a Denial of Service (DoS) by rendering filesystems inaccessible and preventing them from being cleanly unmounted.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.