MEDIUM · 5.5

CVE-2020-11743

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...

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

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
XenXen<= 4.13.0
FedoraprojectFedora32

Related Weaknesses (CWE)

References

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.