CVE-2026-98976
kernel: namespace: keep the lock on a mount that a propagated copy is moved beneath
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 23, 2026
Updated · October 29, 2026
Description
A flaw was found in the Linux kernel. This vulnerability allows information disclosure when filesystem mount locks are improperly handled during mount propagation. When a propagated mount is placed beneath a locked mount and subsequently removed, the covering mount is incorrectly left unlocked. A local user in a user namespace can exploit this flaw to unmount the covering mount and access restricted host files.
CVSS score applicability
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.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 5.6CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
CWE-281 · Improper Preservation of Permissions