Vulnerability Description
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 for success, and a negative number for errors. Some misplaced brackets cause one error path to return 1 instead of a negative value. The grant table code in Linux treats this condition as success, and proceeds with incorrectly initialised state. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to map a grant, it hits the incorrect error path. This will crash a Linux based dom0 or backend domain.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | <= 4.13.0 |
| Fedoraproject | Fedora | 32 |
Related Weaknesses (CWE)
References
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00006.html
- http://www.openwall.com/lists/oss-security/2020/04/14/3PatchThird Party Advisory
- http://xenbits.xen.org/xsa/advisory-316.htmlExploitVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202005-08
- https://www.debian.org/security/2020/dsa-4723
- https://xenbits.xen.org/xsa/advisory-316.htmlExploitVendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00006.html
- http://www.openwall.com/lists/oss-security/2020/04/14/3PatchThird Party Advisory
- http://xenbits.xen.org/xsa/advisory-316.htmlExploitVendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
FAQ
What is CVE-2020-11743?
CVE-2020-11743 is a vulnerability with a CVSS score of 5.5 (MEDIUM). An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 f...
How severe is CVE-2020-11743?
CVE-2020-11743 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2020-11743?
Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen, Fedoraproject Fedora.