xen: information leak in legacy x86 FPU/XMM initialization (XSA-165)
Published Apr 13, 2016
8.6
HIGHCVSS 3.0
EPSS 2.25%
Description
Xen 4.6.x, 4.5.x, 4.4.x, 4.3.x, and earlier do not initialize x86 FPU stack and XMM registers when XSAVE/XRSTOR are not used to manage guest extended register state, which allows local guest domains to obtain sensitive information from other domains via unspecified vectors.
Affected products
No data.
Configuration 2
No data.
Red Hat Enterprise Linux 5
xen
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | xen | Will not fix | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
AV:N/AC:L/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.25% (0.02254) | 82.31th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.25% (0.02254) | 80.59th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.72% (0.00721) | 70.19th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.35% (0.02350) | 74.85th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.72% (0.00721) | 70.82th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.31% (0.00312) | 70.96th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.31% (0.00312) | 69.31th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.31% (0.00312) | 65.37th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.11% (0.01108) | 55.18th | v2 (v2022.01.01) |
| Sep 17, 2022 | 1.11% (0.01108) | 53.57th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.11% (0.01108) | 51.54th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.11% (0.01108) | 29.61th | v2 (v2022.01.01) |
References (11)
- http://support.citrix.com/article/CTX203879 x_refsource_CONFIRM
- http://www.debian.org/security/2016/dsa-3519 vendor-advisoryx_refsource_DEBIAN
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html x_refsource_CONFIRM
- http://www.securityfocus.com/bid/79543 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1034477 vdb-entryx_refsource_SECTRACK
- http://xenbits.xen.org/xsa/advisory-165.html x_refsource_CONFIRMPatchVendor Advisory
- https://access.redhat.com/security/cve/CVE-2015-8555 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1289130 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-8555
- https://security.gentoo.org/glsa/201604-03 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-8555
| Link | Providers | Tags |
|---|---|---|
| http://support.citrix.com/article/CTX203879 | x_refsource_CONFIRM | |
| http://www.debian.org/security/2016/dsa-3519 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html | x_refsource_CONFIRM | |
| http://www.securityfocus.com/bid/79543 | vdb-entryx_refsource_BID | |
| http://www.securitytracker.com/id/1034477 | vdb-entryx_refsource_SECTRACK | |
| http://xenbits.xen.org/xsa/advisory-165.html | x_refsource_CONFIRMPatchVendor Advisory | |
| https://access.redhat.com/security/cve/CVE-2015-8555 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1289130 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2015-8555 | ||
| https://security.gentoo.org/glsa/201604-03 | vendor-advisoryx_refsource_GENTOO | |
| https://www.cve.org/CVERecord?id=CVE-2015-8555 |
Change history (0)
No recorded changes yet.