Improper access control in Xen - CVE-2026-42490
Published: June 9, 2026
Vulnerability identifier: #VU134008
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-42490
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Xen Project
Affected software:
Xen
Xen
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper access control in domctl operations when acquiring the system-wide lock before permission checking for some operations with XSM/Flask in use. A local user can invoke domctl operations that acquire the lock before permission checks to cause a denial of service.
This issue occurs only when XSM/Flask is in use.
How to mitigate CVE-2026-42490
Install security update from vendor's website.