xen: Uncontrolled creation of large page mappings by PV guests on x86
Published Oct 30, 2015
7.2
HIGHCVSS 2.0
EPSS 0.43%
Description
The mod_l2_entry function in arch/x86/mm.c in Xen 3.4 through 4.6.x does not properly validate level 2 page table entries, which allows local PV guest administrators to gain privileges via a crafted superpage mapping.
Affected products
No data.
- 3.4.0
- 3.4.1
- 3.4.2
- 3.4.3
- 3.4.4
- 4.0.0
- 4.0.1
- 4.0.2
- 4.0.3
- 4.0.4
- 4.1.0
- 4.1.1
- 4.1.2
- 4.1.3
- 4.1.4
- 4.1.5
- 4.1.6.1
- 4.2.0
- 4.2.1
- 4.2.2
- 4.2.3
- 4.3.0
- 4.3.1
- 4.3.2
- 4.3.4
- 4.4.0
- 4.4.1
- 4.5.0
- 4.5.1
- 4.6.0
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 mitigation
Running only HVM guests will avoid this vulnerability. On systems where the guest kernel is controlled by the host rather than guest administrator, running only kernels which do not call these hypercalls will also prevent untrusted guest users from exploiting this issue. However untrusted guest administrators can still trigger it unless further steps are taken to prevent them from loading code into the kernel (e.g. by disabling loadable modules etc) or from using other mechanisms which allow them to run code at kernel privilege.
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:C/I:C/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 | 0.43% (0.00427) | 34.63th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.43% (0.00427) | 33.89th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.13% (0.00132) | 30.22th | 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 (16)
- 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/2015-11/msg00063.html vendor-advisoryx_refsource_SUSE
- 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-3390 vendor-advisoryx_refsource_DEBIAN
- http://www.securityfocus.com/bid/77366 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1034032 vdb-entryx_refsource_SECTRACK
- http://xenbits.xen.org/xsa/advisory-148.html x_refsource_CONFIRMVendor Advisory
- https://access.redhat.com/security/cve/CVE-2015-7835 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1271971 Issue Tracking
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-022-2015.txt x_refsource_MISCVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2015-7835
- https://security.gentoo.org/glsa/201604-03 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-7835
Change history (0)
No recorded changes yet.