kernel: unsharing MNT_LOCKED mount can expose files beneath the mount.
Published May 2, 2016
6.1
MEDIUMCVSS 3.0
EPSS 0.33%
Description
fs/namespace.c in the Linux kernel before 4.0.2 processes MNT_DETACH umount2 system calls without verifying that the MNT_LOCKED flag is unset, which allows local users to bypass intended access restrictions and navigate to filesystem locations beneath a mount by calling umount2 within a user namespace.
Affected products
No data.
- ≤ 4.0.1
No data.
Red Hat Enterprise Linux 5
kernel
Not affected
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the Linux kernels as shipped with Red Hat Enterprise Linux 5, 6, 7 and Red Hat Enterprise MRG 2.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
AV:L/AC:L/Au:N/C:P/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.33% (0.00331) | 23.91th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.33% (0.00331) | 24.67th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.03% (0.00026) | 4.25th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.04% (0.00042) | 5.07th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00042) | 5.63th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.28% (0.01282) | 68.34th | v2 (v2022.01.01) |
| Feb 22, 2023 | 1.28% (0.01282) | 68.05th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.28% (0.01282) | 65.91th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.28% (0.01282) | 41.72th | v2 (v2022.01.01) |
References (14)
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce07d891a0891d3c0d0c2d73d577490486b809e1 x_refsource_CONFIRMVendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00054.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00056.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00000.html vendor-advisoryx_refsource_SUSE
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.0.2 x_refsource_CONFIRM
- http://www.openwall.com/lists/oss-security/2015/04/17/4 mailing-listx_refsource_MLIST
- http://www.securityfocus.com/bid/74226 vdb-entryx_refsource_BID
- http://www.spinics.net/lists/linux-containers/msg30786.html mailing-listx_refsource_MLIST
- https://access.redhat.com/security/cve/CVE-2014-9717 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1226751 x_refsource_CONFIRMIssue Tracking
- https://github.com/torvalds/linux/commit/ce07d891a0891d3c0d0c2d73d577490486b809e1 x_refsource_CONFIRMVendor Advisory
- https://groups.google.com/forum/message/raw?msg=linux.kernel/HnegnbXk0Vs/RClojwJzAFEJ mailing-listx_refsource_MLIST
- https://nvd.nist.gov/vuln/detail/CVE-2014-9717
- https://www.cve.org/CVERecord?id=CVE-2014-9717
Change history (0)
No recorded changes yet.