xen: Long latency populate-on-demand operation is not preemptible on x86
Published Oct 30, 2015
4.9
MEDIUMCVSS 2.0
EPSS 0.44%
Description
The p2m_pod_emergency_sweep function in arch/x86/mm/p2m-pod.c in Xen 3.4.x, 3.5.x, and 3.6.x is not preemptible, which allows local x86 HVM guest administrators to cause a denial of service (CPU consumption and possibly reboot) via crafted memory contents that triggers a "time-consuming linear scan," related to Populate-on-Demand.
Affected products
Remediation
Red Hat mitigation
Running only PV guests will avoid this issue. Running HVM guest without enabling Populate-on-Demand mode (so, ensuring that maxmem==memory) will avoid this issue.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:L/AC:L/Au:N/C:N/I:N/A:C
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 (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.44% (0.00436) | 35.63th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.44% (0.00436) | 34.59th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.10% (0.00095) | 24.58th | 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) |
References (14)
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171082.html vendor-advisoryx_refsource_FEDORA
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171185.html vendor-advisoryx_refsource_FEDORA
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171249.html vendor-advisoryx_refsource_FEDORA
- http://lists.opensuse.org/opensuse-updates/2015-12/msg00053.html vendor-advisoryx_refsource_SUSE
- http://support.citrix.com/article/CTX202404 x_refsource_CONFIRM
- http://www.debian.org/security/2015/dsa-3414 vendor-advisoryx_refsource_DEBIAN
- http://www.securityfocus.com/bid/77362 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1034034 vdb-entryx_refsource_SECTRACK
- http://xenbits.xen.org/xsa/advisory-150.html x_refsource_CONFIRMVendor Advisory
- https://access.redhat.com/security/cve/CVE-2015-7970 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1272529 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-7970
- https://security.gentoo.org/glsa/201604-03 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-7970
Change history (0)
No recorded changes yet.