NULL pointer dereference in Xen
CVE-2017-14318
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (34.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 34.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Xen — versions 4.5.0, 4.5.1, 4.5.2
Weakness classification (CWE)
References
- support.citrix.com/article/CTX227185
- www.debian.org/security/2017/dsa-4050 (vendor-advisory)
- www.securitytracker.com/id/1039349 (VDB Entry, Third Party Advisory, vdb-entry)
- xenbits.xen.org/xsa/advisory-232.html (Patch, Vendor Advisory)
- www.securityfocus.com/bid/100817 (VDB Entry, Third Party Advisory, vdb-entry)
Frequently asked questions
- What is CVE-2017-14318?
- CVE-2017-14318 is a medium-severity vulnerability in Xen, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2017-09-12.
- How severe is CVE-2017-14318?
- Medium severity. CVSS v3 base score is 6.5 out of 10.