Vulnerability in Linux

CVE-2025-38499

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.

EPSS: 0.001 (4.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-38499?
CVE-2025-38499 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2025-08-11.
How severe is CVE-2025-38499?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2025-38499 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.