In the Linux kernel, the following vulnerability has been resolved:

clone_private_mnt(): make sure that caller has CAP_SYS_ADMIN in the right userns

What we want is to verify there is that clone won't expose something
hidden by a mount we wouldn't be able to undo. "Wouldn't be able to undo"
may be a result of MNT_LOCKED on a child, but it may also come from
lacking admin rights in the userns of the namespace mount belongs to.

clone_private_mnt() checks the former, but not the latter.

There's a number of rather confusing CAP_SYS_ADMIN checks in various
userns during the mount, especially with the new mount API; they serve
different purposes and in case of clone_private_mnt() they usually,
but not always end up covering the missing check mentioned above.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 28 Aug 2025 14:45:00 +0000


Tue, 12 Aug 2025 07:45:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Vendors & Products Linux
Linux linux Kernel

Tue, 12 Aug 2025 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Mon, 11 Aug 2025 16:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: clone_private_mnt(): make sure that caller has CAP_SYS_ADMIN in the right userns What we want is to verify there is that clone won't expose something hidden by a mount we wouldn't be able to undo. "Wouldn't be able to undo" may be a result of MNT_LOCKED on a child, but it may also come from lacking admin rights in the userns of the namespace mount belongs to. clone_private_mnt() checks the former, but not the latter. There's a number of rather confusing CAP_SYS_ADMIN checks in various userns during the mount, especially with the new mount API; they serve different purposes and in case of clone_private_mnt() they usually, but not always end up covering the missing check mentioned above.
Title clone_private_mnt(): make sure that caller has CAP_SYS_ADMIN in the right userns
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-08-28T14:43:32.428Z

Reserved: 2025-04-16T04:51:24.022Z

Link: CVE-2025-38499

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-08-11T16:15:30.057

Modified: 2025-08-28T15:15:51.383

Link: CVE-2025-38499

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-08-11T00:00:00Z

Links: CVE-2025-38499 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-08-12T07:41:42Z