CVE-2026-23558

EUVD-2026-30928
The adjustments made for XSA-379 as well as those subsequently becoming
XSA-387 still left a race window, when a HVM or PVH guest does a grant
table version change from v2 to v1 in parallel with mapping the status
page(s) via XENMEM_add_to_physmap.  Some of the status pages may then be
freed while mappings of them would still be inserted into the guest's
secondary (P2M) page tables.
Race Condition
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.8 HIGH
LOCAL
HIGH
LOW
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 1.97%
Affected Products (NVD)
VendorProductVersion
xenxen
4.0.0 ≤
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
xen
bookworm
no-dsa
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
vulnerable
forky
4.20.3+127-gc42374a105-1
fixed
sid
4.20.3+127-gc42374a105-1
fixed
trixie
vulnerable
trixie (security)
4.20.3+127-gc42374a105-0+deb13u1
fixed
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
References
https://xenbits.xenproject.org/xsa/advisory-486.html
http://www.openwall.com/lists/oss-security/2026/04/28/13
http://xenbits.xen.org/xsa/advisory-486.html