MEDIUM
The KEYS subsystem in the Linux kernel before 4.10.13 allows local users to cause a denial of service (memory consumption) via a series of KEY_REQKEY_DEFL_THREAD_KEYRING keyctl_set_reqkey_keyring calls.
http://lists.opensuse.org/opensuse-security-announce/2018-01/msg00007.html
http://openwall.com/lists/oss-security/2017/05/11/1
http://www.securityfocus.com/bid/98422
http://www.securitytracker.com/id/1038471
https://access.redhat.com/errata/RHSA-2018:0151
https://access.redhat.com/errata/RHSA-2018:0152
https://access.redhat.com/errata/RHSA-2018:0181
https://bugzilla.novell.com/show_bug.cgi?id=1034862
https://bugzilla.redhat.com/show_bug.cgi?id=1442086
https://github.com/torvalds/linux/commit/c9f838d104fed6f2f61d68164712e3204bf5271b
https://lkml.org/lkml/2017/4/1/235
https://lkml.org/lkml/2017/4/3/724
https://www.exploit-db.com/exploits/42136/
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.10.13
Source: MITRE
Published: 2017-05-11
Updated: 2018-01-27
Type: CWE-399
Base Score: 4.9
Vector: (AV:L/AC:L/Au:N/C:N/I:N/A:C)
Impact Score: 6.9
Exploitability Score: 3.9
Severity: MEDIUM
Base Score: 5.5
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 1.8
Severity: MEDIUM