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.
References (11)
Core 11
Core References
Mailing List vendor-advisory
x_refsource_suse
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00054.html
Mailing List vendor-advisory
x_refsource_suse
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00056.html
Vendor Advisory x_refsource_confirm
https://github.com/torvalds/linux/commit/ce07d891a0891d3c0d0c2d73d577490486b809e1
Mailing List mailing-list
x_refsource_mlist
http://www.openwall.com/lists/oss-security/2015/04/17/4
Vendor Advisory x_refsource_confirm
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce07d891a0891d3c0d0c2d73d577490486b809e1
Issue Tracking x_refsource_confirm
https://bugzilla.redhat.com/show_bug.cgi?id=1226751
Mailing List mailing-list
x_refsource_mlist
https://groups.google.com/forum/message/raw?msg=linux.kernel/HnegnbXk0Vs/RClojwJzAFEJ
Various Sources mailing-list
x_refsource_mlist
http://www.spinics.net/lists/linux-containers/msg30786.html
Third Party Advisory, VDB Entry vdb-entry
x_refsource_bid
http://www.securityfocus.com/bid/74226
Vendor Advisory x_refsource_confirm
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.0.2
Mailing List vendor-advisory
x_refsource_suse
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00000.html
Scores
CVSS v3
6.1
EPSS
0.0033
EPSS Percentile
25.0%
Attack Vector
LOCAL
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Details
CWE
CWE-284
Status
published
Products (1)
linux/linux_kernel
< 4.0.1
Published
May 02, 2016
Tracked Since
Feb 18, 2026