Medium severity · published Oct 7, 2016
CVE-2016-7777
Xen 4.7.x and earlier does not properly honor CR0.TS and CR0.EM, which allows local x86 HVM guest OS users to read or modify FPU, MMX, or XMM register state information belonging…
6.3
CVSS
0.3%
EPSS
No
On KEV
Description
Xen 4.7.x and earlier does not properly honor CR0.TS and CR0.EM, which allows local x86 HVM guest OS users to read or modify FPU, MMX, or XMM register state information belonging to arbitrary tasks on the guest by modifying an instruction while the hypervisor is preparing to emulate it.
CVSS vector
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
XE
Xen · Xen
through 4.7.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2016-7777
CVE.org
https://www.cve.org/CVERecord?id=CVE-2016-7777
Third Party Advisory
http://www.securityfocus.com/bid/93344
Third Party Advisory
http://www.securitytracker.com/id/1036942
Mitigation
http://xenbits.xen.org/xsa/advisory-190.html
security.gentoo.org
https://security.gentoo.org/glsa/201611-09
support.citrix.com
https://support.citrix.com/article/CTX217363
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