NULL Pointer Dereference Affecting xen package, versions <4.8.2+xsa245-0+deb9u1
Threat Intelligence
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Start learning- Snyk IDSNYK-DEBIAN12-XEN-1564460
- published12 Sept 2017
- disclosed12 Sept 2017
Introduced: 12 Sep 2017
CVE-2017-14318 (opens in a new tab)How to fix?
Upgrade Debian:12 xen to version 4.8.2+xsa245-0+deb9u1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream xen package and not the xen package as distributed by Debian.
See How to fix? for Debian:12 relevant fixed versions and status.
An issue was discovered in Xen 4.5.x through 4.9.x. The function __gnttab_cache_flush handles GNTTABOP_cache_flush grant table operations. It checks to see if the calling domain is the owner of the page that is to be operated on. If it is not, the owner's grant table is checked to see if a grant mapping to the calling domain exists for the page in question. However, the function does not check to see if the owning domain actually has a grant table or not. Some special domains, such as DOMID_XEN, DOMID_IO and DOMID_COW are created without grant tables. Hence, if __gnttab_cache_flush operates on a page owned by these special domains, it will attempt to dereference a NULL pointer in the domain struct.
References
- https://security-tracker.debian.org/tracker/CVE-2017-14318
- https://www.debian.org/security/2017/dsa-4050
- https://support.citrix.com/article/CTX227185
- http://xenbits.xen.org/xsa/advisory-232.html
- http://www.securityfocus.com/bid/100817
- http://www.securitytracker.com/id/1039349
- http://people.ubuntu.com/~ubuntu-security/cve/CVE-2017-14318