MEDIUM
The xsave/xrstor implementation in arch/x86/include/asm/xsave.h in the Linux kernel before 3.19.2 creates certain .altinstr_replacement pointers and consequently does not provide any protection against instruction faulting, which allows local users to cause a denial of service (panic) by triggering a fault, as demonstrated by an unaligned memory operand or a non-canonical address memory operand.
http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.19.2
http://www.openwall.com/lists/oss-security/2015/03/22/1
https://bugzilla.redhat.com/show_bug.cgi?id=1204729
https://github.com/torvalds/linux/commit/06c8173eb92bbfc03a0fe8bb64315857d0badd06
Source: MITRE
Published: 2016-05-02
Updated: 2016-05-06
Type: CWE-20
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