An issue was discovered in Xen through 4.11.x. The DEBUGCTL MSR contains several debugging features, some of which virtualise cleanly, but some do not. In particular, Branch Trace Store is not virtualised by the processor, and software has to be careful to configure it suitably not to lock up the core. As a result, it must only be available to fully trusted guests. Unfortunately, in the case that vPMU is disabled, all value checking was skipped, allowing the guest to choose any MSR_DEBUGCTL setting it likes. A malicious or buggy guest administrator (on Intel x86 HVM or PVH) can lock up the entire host, causing a Denial of Service.
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2018-08-17T17:00:00

Updated: 2024-08-05T09:54:03.455Z

Reserved: 2018-08-17T00:00:00

Link: CVE-2018-15468

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2018-08-17T18:29:00.740

Modified: 2019-10-03T00:03:26.223

Link: CVE-2018-15468

cve-icon Redhat

Severity : Moderate

Publid Date: 2018-08-14T17:00:00Z

Links: CVE-2018-15468 - Bugzilla