CVE-2020-15563: Buffer Overflow
An issue was discovered in Xen through 4.13.x, allowing x86 HVM guest OS users to cause a hypervisor crash. An inverted conditional in x86 HVM guests' dirty video RAM tracking code allows such guests to make Xen de-reference a pointer guaranteed to point at unmapped space. A malicious or buggy HVM guest may cause the hypervisor to crash, resulting in Denial of Service (DoS) affecting the entire host. Xen versions from 4.8 onwards are affected. Xen versions 4.7 and earlier are not affected. Only x86 systems are affected. Arm systems are not affected. Only x86 HVM guests using shadow paging can leverage the vulnerability. In addition, there needs to be an entity actively monitoring a guest's video frame buffer (typically for display purposes) in order for such a guest to be able to leverage the vulnerability. x86 PV guests, as well as x86 HVM guests using hardware assisted paging (HAP), cannot leverage the vulnerability.
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is CVE-2020-15563?
CVE-2020-15563 is a vulnerability in Xen that allows x86 HVM guest OS users to cause a hypervisor crash.
How does CVE-2020-15563 work?
CVE-2020-15563 works by exploiting an inverted conditional in x86 HVM guests' dirty video RAM tracking code, allowing guests to make Xen de-reference a pointer that points to unmapped space.
What is the severity of CVE-2020-15563?
The severity of CVE-2020-15563 is not specified in the provided information.
Which software versions are affected by CVE-2020-15563?
Versions 4.11.3+24- and earlier of Xen on Ubuntu, and versions 4.11.4+107-gef32c7afa2-1, 4.14.5+94-ge49571868d-1, 4.17.1+2-gb773c48e36-1, and 4.17.2-1 and earlier of Xen on Debian are affected.
How can CVE-2020-15563 be fixed?
To fix CVE-2020-15563, apply the recommended patches provided by the vendor for your specific Xen version.