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 to arbitrary tasks on the guest by modifying an instruction while the…
Does this matter?
Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own.
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 3.0
- 6.3 MEDIUMCVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.30% probability · 23th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-362
- Affected
- xen/xen
- Source
- cve@mitre.org
EPSS 0.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/93344Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1036942Third Party Advisory, VDB Entry
- http://xenbits.xen.org/xsa/advisory-190.htmlMitigation, Patch, Vendor Advisory
- https://security.gentoo.org/glsa/201611-09
- https://support.citrix.com/article/CTX217363
- http://www.securityfocus.com/bid/93344Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1036942Third Party Advisory, VDB Entry
- http://xenbits.xen.org/xsa/advisory-190.htmlMitigation, Patch, Vendor Advisory
- https://security.gentoo.org/glsa/201611-09
- https://support.citrix.com/article/CTX217363
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.