4.9 Medium
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:N/I:N/A:C
6 Medium
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
0.001 Low
EPSS
Percentile
26.7%
Both writes to the FS and GS register base MSRs as well as the WRFSBASE and WRGSBASE instructions require their input values to be canonical, or a #GP fault will be raised. When the use of those instructions by the hypervisor was enabled, the previous guard against #GP faults (having recovery code attached) was accidentally removed.
A malicious guest administrator can crash the host, leading to a DoS.
Xen versions 4.4 and onwards are affected. Xen versions 4.3 and earlier are not affected.
The vulnerability is only exposed to x86 PV guests.
The vulnerability is NOT exposed to x86 HVM guests.
ARM systems are NOT vulnerable.
4.9 Medium
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:L/AC:L/Au:N/C:N/I:N/A:C
6 Medium
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
0.001 Low
EPSS
Percentile
26.7%