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
CWE
Assigner
XEN
References
Impacted products
Vendor Product Version
Xen Xen Unknown: consult Xen advisory XSA-481
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
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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