HIGH
xen: broken x86 shadow mode refcount overflow check (XSA-249)
Published Dec 12, 2017
7.8
HIGHCVSS 3.0
EPSS 0.35%
Description
An issue was discovered in Xen through 4.9.x allowing guest OS users to cause a denial of service (host OS crash) or gain host OS privileges by leveraging an incorrect mask for reference-count overflow checking in shadow mode.
Affected products
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
7.8 HIGH NVD
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector Local
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Changed
Confidentiality Impact High
Integrity Impact High
Availability Impact High
6.9 MEDIUM NVD
AV:L/AC:M/Au:N/C:C/I:C/A:C
Access Vector Local
Access Complexity Medium
Authentication None
Confidentiality Impact Complete
Integrity Impact Complete
Availability Impact Complete
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
0.35% 0.00352
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.00352
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (14 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.35% (0.00352) | 26.45th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.35% (0.00352) | 26.81th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.06% (0.00064) | 17.26th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.06% (0.00062) | 28.60th | v3 (v2023.03.01) |
| Jun 13, 2024 | 0.06% (0.00062) | 26.61th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.06% (0.00062) | 24.59th | 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) |
| Feb 3, 2022 | 2.57% (0.02567) | 55.02th | v1 |
| Jan 6, 2022 | 2.57% (0.02567) | 54.58th | v1 |
| Sep 1, 2021 | 2.57% (0.02567) | 78.88th | v1 |
| Apr 14, 2021 | 2.57% (0.02567) | 0.00th | v1 |
Weaknesses (1)
References (14)
- http://www.openwall.com/lists/oss-security/2017/12/12/2 x_refsource_CONFIRMMailing List
- http://www.securityfocus.com/bid/102169 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1040769 vdb-entryx_refsource_SECTRACK
- http://xenbits.xen.org/xsa/advisory-249.html
- https://access.redhat.com/security/cve/CVE-2017-17563 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1518657 Issue Tracking
- https://lists.debian.org/debian-lts-announce/2018/01/msg00003.html mailing-listx_refsource_MLIST
- https://lists.debian.org/debian-lts-announce/2018/10/msg00009.html mailing-listx_refsource_MLIST
- https://nvd.nist.gov/vuln/detail/CVE-2017-17563
- https://security.gentoo.org/glsa/201801-14 vendor-advisoryx_refsource_GENTOO
- https://support.citrix.com/article/CTX232096 x_refsource_CONFIRM
- https://www.cve.org/CVERecord?id=CVE-2017-17563
- https://www.debian.org/security/2018/dsa-4112 vendor-advisoryx_refsource_DEBIAN
- https://xenbits.xen.org/xsa/advisory-249.html x_refsource_CONFIRMMitigationPatchVendor Advisory
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Dec 12, 2017
Updated Aug 5, 2024
Reserved Dec 12, 2017
Link CVE-2017-17563
CISA Vulnrichment
Updated n/a