Description

A grant unmapping issue was discovered in Xen through 4.9.x. When removing or replacing a grant mapping, the x86 PV specific path needs to make sure page table entries remain in sync with other accounting done. Although the identity of the page frame was validated correctly, neither the presence of the mapping nor page writability were taken into account.

References

http://www.securityfocus.com/bid/100819

http://www.securitytracker.com/id/1039351

http://xenbits.xen.org/xsa/advisory-234.html

https://lists.debian.org/debian-lts-announce/2018/10/msg00009.html

https://support.citrix.com/article/CTX227185

https://www.debian.org/security/2017/dsa-4050

Details

Risk Information

CVSS v2

CVSS v3