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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…
Medium6.3EPSS 0.30%
- Published
- Updated
- Reserved
- Assigned by
- mitre
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.
Timeline
ID reserved
By mitre
- 28 days later
· 28 days later
Published
- 8 years later
· 8 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Medium6.3 | CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.30% · top 77% of all CVEs (8 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.3.
Weakness
Affected products
n/a
- affected n/a
References (5)
- https://support.citrix.com/article/CTX217363 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://xenbits.xen.org/xsa/advisory-190.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- 93344 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- GLSA-201611-09 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- 1036942 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2016-7777)Record last updated .