4.6 Medium
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:L/AC:L/Au:S/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:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
0.0004 Low
EPSS
Percentile
14.4%
An issue was discovered in Xen through 4.14.x. An x86 PV guest can trigger
a host OS crash when handling guest access to MSR_MISC_ENABLE. When a guest
accesses certain Model Specific Registers, Xen first reads the value from
hardware to use as the basis for auditing the guest access. For the
MISC_ENABLE MSR, which is an Intel specific MSR, this MSR read is performed
without error handling for a #GP fault, which is the consequence of trying
to read this MSR on non-Intel hardware. A buggy or malicious PV guest
administrator can crash Xen, resulting in a host Denial of Service. Only
x86 systems are vulnerable. ARM systems are not vulnerable. Only Xen
versions 4.11 and onwards are vulnerable. 4.10 and earlier are not
vulnerable. Only x86 systems that do not implement the MISC_ENABLE MSR
(0x1a0) are vulnerable. AMD and Hygon systems do not implement this MSR and
are vulnerable. Intel systems do implement this MSR and are not vulnerable.
Other manufacturers have not been checked. Only x86 PV guests can exploit
the vulnerability. x86 HVM/PVH guests cannot exploit the vulnerability.
Author | Note |
---|---|
mdeslaur | hypervisor packages are in universe. For issues in the hypervisor, add appropriate tags to each section, ex: Tags_xen: universe-binary |
launchpad.net/bugs/cve/CVE-2020-25602
lists.fedoraproject.org/archives/list/[email protected]/message/4JRXMKEMQRQYWYEPHVBIWUEAVQ3LU4FN/
nvd.nist.gov/vuln/detail/CVE-2020-25602
security-tracker.debian.org/tracker/CVE-2020-25602
ubuntu.com/security/notices/USN-5617-1
www.cve.org/CVERecord?id=CVE-2020-25602
xenbits.xen.org/xsa/advisory-333.html
4.6 Medium
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
COMPLETE
AV:L/AC:L/Au:S/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:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
0.0004 Low
EPSS
Percentile
14.4%