xen: AMD FPU FIP/FDP/FOP leak workaround broken (XSA-172)
Published Apr 13, 2016
3.8
LOWCVSS 3.0
EPSS 0.40%
Description
The fpu_fxrstor function in arch/x86/i387.c in Xen 4.x does not properly handle writes to the hardware FSW.ES bit when running on AMD64 processors, which allows local guest OS users to obtain sensitive register content information from another guest by leveraging pending exception and mask bits. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-2076.
Affected products
No data.
Configuration 2
Configuration 3
- 22
- 23
Configuration 4
- 8.0
No data.
Red Hat Enterprise Linux 5
xen
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | xen | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the Xen hypervisor packages as shipped with Red Hat Enterprise Linux 5.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
AV:L/AC:L/Au:S/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 (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.40% (0.00399) | 31.74th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.40% (0.00399) | 31.50th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.04% (0.00041) | 9.37th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.15% (0.00153) | 52.93th | v3 (v2023.03.01) |
| Jul 14, 2024 | 0.10% (0.00102) | 42.33th | v3 (v2023.03.01) |
| Jun 11, 2024 | 0.10% (0.00095) | 40.19th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.05% (0.00054) | 19.77th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.28% (0.01282) | 68.34th | v2 (v2022.01.01) |
| Feb 22, 2023 | 1.28% (0.01282) | 68.05th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.28% (0.01282) | 65.91th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.28% (0.01282) | 41.72th | v2 (v2022.01.01) |
References (13)
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181699.html vendor-advisoryx_refsource_FEDORAMailing ListThird Party Advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2016-April/181729.html vendor-advisoryx_refsource_FEDORAMailing ListThird Party Advisory
- http://support.citrix.com/article/CTX209443 x_refsource_CONFIRMThird Party Advisory
- http://www.debian.org/security/2016/dsa-3554 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html x_refsource_CONFIRMThird Party Advisory
- http://www.securityfocus.com/bid/85716 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1035435 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- http://xenbits.xen.org/xsa/advisory-172.html x_refsource_CONFIRMPatchVendor Advisory
- http://xenbits.xen.org/xsa/xsa172.patch x_refsource_CONFIRMPatchVendor Advisory
- https://access.redhat.com/security/cve/CVE-2016-3159 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1317969 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2016-3159
- https://www.cve.org/CVERecord?id=CVE-2016-3159
Change history (0)
No recorded changes yet.