CVE-2015-7835
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 2.0
- 7.2 HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
- EPSS
- 0.43% probability · 37th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20, CWE-264
- Affected
- xen/xen
- Source
- cve@mitre.org
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171082.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171185.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171249.html
- http://lists.opensuse.org/opensuse-updates/2015-11/msg00063.html
- http://lists.opensuse.org/opensuse-updates/2015-12/msg00053.html
- http://support.citrix.com/article/CTX202404
- http://www.debian.org/security/2015/dsa-3390
- http://www.securityfocus.com/bid/77366
- http://www.securitytracker.com/id/1034032
- http://xenbits.xen.org/xsa/advisory-148.htmlVendor Advisory
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-022-2015.txtVendor Advisory
- https://security.gentoo.org/glsa/201604-03
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171082.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171185.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-November/171249.html
- http://lists.opensuse.org/opensuse-updates/2015-11/msg00063.html
- http://lists.opensuse.org/opensuse-updates/2015-12/msg00053.html
- http://support.citrix.com/article/CTX202404
- http://www.debian.org/security/2015/dsa-3390
- http://www.securityfocus.com/bid/77366
- http://www.securitytracker.com/id/1034032
- http://xenbits.xen.org/xsa/advisory-148.htmlVendor Advisory
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-022-2015.txtVendor Advisory
- https://security.gentoo.org/glsa/201604-03
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.