CVE-2026-23555 — HIGH (7.1)

Vulnerability Description

Any guest issuing a Xenstore command accessing a node using the (illegal) node path "/local/domain/", will crash xenstored due to a clobbered error indicator in xenstored when verifying the node path. Note that the crash is forced via a failing assert() statement in xenstored. In case xenstored is being built with NDEBUG #defined, an unprivileged guest trying to access the node path "/local/domain/" will result in it no longer being serviced by xenstored, other guests (including dom0) will still be serviced, but xenstored will use up all cpu time it can get.

CVSS Score

7.1

HIGH

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

CHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Xen	Xen	>= 4.18.0

Related Weaknesses (CWE)

CWE-617

References

https://xenbits.xenproject.org/xsa/advisory-481.htmlPatchVendor Advisory
http://www.openwall.com/lists/oss-security/2026/03/17/7Mailing ListPatchThird Party Advisory
http://xenbits.xen.org/xsa/advisory-481.htmlPatchVendor Advisory

FAQ

What is CVE-2026-23555?

CVE-2026-23555 is a vulnerability with a CVSS score of 7.1 (HIGH). Any guest issuing a Xenstore command accessing a node using the (illegal) node path "/local/domain/", will crash xenstored due to a clobbered error indicator in xenstored when verifying the node path....

How severe is CVE-2026-23555?

CVE-2026-23555 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-23555?

Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen.