Xen through 4.8.x does not validate memory allocations during certain P2M operations, which allows guest OS users to obtain privileged host OS access, aka XSA-222.
Severity
CVSS 3.0
10.0 critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
3.7% chance of exploitation in the next 30 days; higher than 89% of CVEs (scores of 2026-10-31)