CVE-2018-15468: xen Incorrect Authorization
Vulnerability summary
CVE-2018-15468 is a medium (CVSS 6.0) Incorrect Authorization vulnerability in xen. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.2% of scored vulnerabilities.
Not severe (CVSS 6, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 5 · Related 4Timeline
- 17-08-2018PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated6.0MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated6.0MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.0MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
EPSS trend
Probability
0.34%
Chance of exploitation in the next 30 days
Percentile
27%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.34% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, administrative account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- xen< 4.11.1-r0 | < 4.8.5-r0 | < 4.9.3-r0 | < 4.10.1-r3
Debian1 product
- xen< 4.11.1~pre.20180911.5acdd26fdc+dfsg-2
Ubuntu1 product
- xenAll versions (No fix recorded)
Xen1 product
- xen≤ 4.11.0
4 vendors · 4 products
