Vulnerability Description
Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The management of the bitmap underlying that operation is tied into the binding of the VIRQ_DOM_EXC virtual IRQ. Unfortunately an error path there would tear down the bitmap even in cases when it wasn't set up. Unprivileged domains can trigger that error path.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://xenbits.xenproject.org/xsa/advisory-496.html
- http://www.openwall.com/lists/oss-security/2026/07/28/13
- http://xenbits.xen.org/xsa/advisory-496.html
FAQ
What is CVE-2026-42492?
CVE-2026-42492 is a vulnerability with a CVSS score of 7.5 (HIGH). Xenstore, to have an up-to-date picture of the entire system, wants to know of domains appearing and disappearing. To make this more robust, a new XEN_DOMCTL_get_domain_state was introduced. The man...
How severe is CVE-2026-42492?
CVE-2026-42492 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-42492?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.