CVE-2026-42490
CWE-667Published: June 18, 2026· Updated: Jun 22, 2026
Official Description
[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.
Technical Analysis
CVE-2026-42490 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Exploit & PoC Resources
All References (1)
Quick Facts
Related CVEs (CWE-667)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-42490 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts