[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]
To create and manage guests, domctl operations are used by the control domain, a possible Xenstore domain, or by a domain controlling a particular guest. Some of these operations may not be executed in parallel, so a system-wide lock is used. The way that lock is acquired is, however, not providing any fairness. This is CVE-2026-42489.
Furthermore, with XSM/Flask in use, the lock acquire will, for some operations, occur ahead of any permission checking. This is CVE-2026-42490.
Exploitability
AV:LAC:HPR:HUI:NScope
S:CImpact
C:NI:NA:H5.3/CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:N/A:H