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.
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 |
Priority
Status
Package | Release | Status |
---|---|---|
xen Launchpad, Ubuntu, Debian |
hirsute |
Ignored
(end of life)
|
groovy |
Ignored
(end of life)
|
|
impish |
Ignored
(end of life)
|
|
focal |
Not vulnerable
(4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10)
|
|
jammy |
Not vulnerable
(4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10)
|
|
kinetic |
Not vulnerable
(4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10)
|
|
bionic |
Needed
|
|
cosmic |
Ignored
(end of life)
|
|
disco |
Ignored
(end of life)
|
|
eoan |
Ignored
(end of life)
|
|
lunar |
Not vulnerable
(4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10)
|
|
trusty |
Does not exist
(trusty was needs-triage)
|
|
upstream |
Released
(4.11.1~pre.20180911.5acdd26fdc+dfsg-2)
|
|
xenial |
Needed
|
|
mantic |
Not vulnerable
(4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10)
|
|
Binaries built from this source package are in Universe and so are supported by the community. |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 6.0 |
Attack vector | Local |
Attack complexity | Low |
Privileges required | High |
User interaction | None |
Scope | Changed |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H |