CVE-2017-14318 Null dereference in n/a
A missing check in Xen's grant table handling causes a NULL pointer dereference when flushing cache for special domains, leading to a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2017-14318?
CVE-2017-14318 is a medium-severity vulnerability in Xen Xen, published on 12 Sep 2017. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-476
Which versions are affected by CVE-2017-14318?
It affects 1 product.
Products include Xen Xen.
How do I fix CVE-2017-14318?
Apply the vendor's patch.
Is CVE-2017-14318 being exploited?
There is no known exploitation of CVE-2017-14318 in the wild and no public exploit code.
Other vulnerabilities in Xen Xen
Sources
Also known as ALPINE-CVE-2017-14318, DEBIAN-CVE-2017-14318, GHSA-g75p-4v96-pxff, UBUNTU-CVE-2017-14318.