Vulnerability Description
certain VT-d IOMMUs may not work in shared page table mode For efficiency reasons, address translation control structures (page tables) may (and, on suitable hardware, by default will) be shared between CPUs, for second-level translation (EPT), and IOMMUs. These page tables are presently set up to always be 4 levels deep. However, an IOMMU may require the use of just 3 page table levels. In such a configuration the lop level table needs to be stripped before inserting the root table's address into the hardware pagetable base register. When sharing page tables, Xen erroneously skipped this stripping. Consequently, the guest is able to write to leaf page table entries.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | 4.15.0 |
| Fedoraproject | Fedora | 35 |
Related Weaknesses (CWE)
References
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202208-23Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-390.txtVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202208-23Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-390.txtVendor Advisory
FAQ
What is CVE-2021-28710?
CVE-2021-28710 is a vulnerability with a CVSS score of 8.8 (HIGH). certain VT-d IOMMUs may not work in shared page table mode For efficiency reasons, address translation control structures (page tables) may (and, on suitable hardware, by default will) be shared betwe...
How severe is CVE-2021-28710?
CVE-2021-28710 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-28710?
Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen, Fedoraproject Fedora.