CVE-2026-42488

EUVD-2026-37891
Some shadow paging errors paths will switch the page-tables without
updating the currently running vCPU reference.  This causes a mismatch
between the loaded page-tables and the mapcache metadata which can lead
to corruption of the mapcache.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 28%
Debian logo
Debian Releases
Debian Product
Codename
xen
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
vulnerable
forky
vulnerable
sid
4.20.3+127-gc42374a105-1
fixed
trixie
vulnerable
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
xen
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
questing
ignored
resolute
needs-triage
xenial
needs-triage
Common Weakness Enumeration
Vulnerability Media Exposure
References
https://xenbits.xenproject.org/xsa/advisory-494.html
http://www.openwall.com/lists/oss-security/2026/06/09/14
http://xenbits.xen.org/xsa/advisory-494.html