Race condition in the grant table code in Xen 4.6.x through 4.9.x allows local guest OS administrators to cause a denial of service (free list corruption and host crash) or gain privileges on the host via vectors involving maptrack free list handling.
CVSS Score
7.8
EPSS Score
0.001
Published
2017-08-24
arch/x86/mm.c in Xen allows local PV guest OS users to gain host OS privileges via vectors related to map_grant_ref.
CVSS Score
8.8
EPSS Score
0.001
Published
2017-08-24
Xen maintains the _GTF_{read,writ}ing bits as appropriate, to inform the guest that a grant is in use. A guest is expected not to modify the grant details while it is in use, whereas the guest is free to modify/reuse the grant entry when it is not in use. Under some circumstances, Xen will clear the status bits too early, incorrectly informing the guest that the grant is no longer in use. A guest may prematurely believe that a granted frame is safely private again, and reuse it in a way which contains sensitive information, while the domain on the far end of the grant is still using the grant. Xen 4.9, 4.8, 4.7, 4.6, and 4.5 are affected.
CVSS Score
6.5
EPSS Score
0.001
Published
2017-08-15
Xen through 4.8.x mishandles page transfer, which allows guest OS users to obtain privileged host OS access, aka XSA-217.
CVSS Score
10.0
EPSS Score
0.017
Published
2017-07-05
The grant-table feature in Xen through 4.8.x provides false mapping information in certain cases of concurrent unmap calls, which allows backend attackers to obtain sensitive information or gain privileges, aka XSA-218 bug 1.
CVSS Score
9.8
EPSS Score
0.012
Published
2017-07-05
The grant-table feature in Xen through 4.8.x has a race condition leading to a double free, which allows guest OS users to cause a denial of service (memory consumption), or possibly obtain sensitive information or gain privileges, aka XSA-218 bug 2.
CVSS Score
8.1
EPSS Score
0.006
Published
2017-07-05
The shadow-paging feature in Xen through 4.8.x mismanages page references and consequently introduces a race condition, which allows guest OS users to obtain Xen privileges, aka XSA-219.
CVSS Score
9.0
EPSS Score
0.005
Published
2017-07-05
The vCPU context-switch implementation in Xen through 4.8.x improperly interacts with the Memory Protection Extensions (MPX) and Protection Key (PKU) features, which makes it easier for guest OS users to defeat ASLR and other protection mechanisms, aka XSA-220.
CVSS Score
7.5
EPSS Score
0.004
Published
2017-07-05
Xen through 4.8.x does not validate the port numbers of polled event channel ports, which allows guest OS users to cause a denial of service (NULL pointer dereference and host OS crash) or possibly obtain sensitive information, aka XSA-221.
CVSS Score
9.1
EPSS Score
0.008
Published
2017-07-05
Xen through 4.8.x does not validate memory allocations during certain P2M operations, which allows guest OS users to obtain privileged host OS access, aka XSA-222.
CVSS Score
10.0
EPSS Score
0.017
Published
2017-07-05