GNTTABOP_swap_grant_ref in Xen 4.2 through 4.5 does not check the grant table operation version, which allows local guest domains to cause a denial of service (NULL pointer dereference) via a hypercall without a GNTTABOP_setup_table or GNTTABOP_set_version.
http://lists.opensuse.org/opensuse-security-announce/2015-06/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2015-06/msg00007.html
http://lists.opensuse.org/opensuse-security-announce/2015-06/msg00030.html
http://support.citrix.com/article/CTX201145
http://www.debian.org/security/2015/dsa-3286
http://www.securityfocus.com/bid/75141
http://www.securitytracker.com/id/1032568
http://xenbits.xen.org/xsa/advisory-134.html
Source: MITRE
Published: 2015-06-15
Updated: 2018-10-30
Type: NVD-CWE-Other
Base Score: 4.9
Vector: AV:L/AC:L/Au:N/C:N/I:N/A:C
Impact Score: 6.9
Exploitability Score: 3.9
Severity: MEDIUM