CVE-2018-15468
Published: 17 August 2018
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.
Priority
Medium
CVSS 3 base score: 6.0
Status
| Package | Release | Status |
|---|---|---|
|
xen Launchpad, Ubuntu, Debian |
Upstream |
Released
(4.11.1~pre.20180911.5acdd26fdc+dfsg-2)
|
| Ubuntu 21.04 (Hirsute Hippo) |
Needed
|
|
| Ubuntu 20.04 LTS (Focal Fossa) |
Needed
|
|
| Ubuntu 18.04 LTS (Bionic Beaver) |
Needed
|
|
| Ubuntu 16.04 ESM (Xenial Xerus) |
Needed
|
|
| Ubuntu 14.04 ESM (Trusty Tahr) |
Does not exist
(trusty was needs-triage)
|
|
| Binaries built from this source package are in Universe and so are supported by the community. | ||
Notes
| Author | Note |
|---|---|
| mdeslaur | hypervisor packages are in universe. For issues in the hypervisor, add appropriate tags to each section, ex: Tags_xen: universe-binary |