CVE-2026-23555 (GCVE-0-2026-23555)

Vulnerability from cvelistv5 – Published: 2026-03-23 06:57 – Updated: 2026-03-23 14:14
VLAI
Title
Xenstored DoS by unprivileged domain
Summary
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.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 14:11 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-481
guessed Create a notification for this product.
Date Public
2026-03-17 12:00
Credits
This issue was discovered by Marek Marczykowski-Góreckiof Invisible Things Lab.
Show details on NVD website
To clipboard 

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