xen: populate-on-demand balloon size inaccuracy can crash guests on x86
Published Oct 30, 2015
2.1
LOWCVSS 2.0
EPSS 0.43%
Description
The (1) libxl_set_memory_target function in tools/libxl/libxl.c and (2) libxl__build_post function in tools/libxl/libxl_dom.c in Xen 3.4.x through 4.6.x do not properly calculate the balloon size when using the populate-on-demand (PoD) system, which allows local HVM guest users to cause a denial of service (guest crash) via unspecified vectors related to "heavy memory pressure."
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
Reducing the guest's memory target, after guest startup, can cause the guest's ballon driver to eliminate the PoD discrepancy. If the guest successfully balloons down, it will no longer be vulnerable.
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:P
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% (0.00426) | 34.52th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.43% (0.00426) | 33.78th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.09% (0.00093) | 24.05th | 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/2015-11/msg00063.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/77365 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1034036 vdb-entryx_refsource_SECTRACK
- http://xenbits.xen.org/xsa/advisory-153.html x_refsource_CONFIRMVendor Advisory
- https://access.redhat.com/security/cve/CVE-2015-7972 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1276120 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-7972
- https://security.gentoo.org/glsa/201604-03 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-7972
Change history (0)
No recorded changes yet.