CVE-2026-23557 (GCVE-0-2026-23557)

Vulnerability from cvelistv5 – Published: 2026-05-19 12:49 – Updated: 2026-05-19 14:42
VLAI
Title
Xenstored DoS via XS_RESET_WATCHES command
Summary
Any guest can cause xenstored to crash by issuing a XS_RESET_WATCHES command within a transaction due to an assert() triggering. In case xenstored was built with NDEBUG #defined nothing bad will happen, as assert() is doing nothing in this case. Note that the default is not to define NDEBUG for xenstored builds even in release builds of Xen.
Severity
6.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/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 2026-05-19 14:42 UTC
CWE
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 46 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-484
guessed Create a notification for this product.
Date Public
2026-04-28 12:00
Credits
This issue was discovered by Andrii Sultanov of Vates.
Show details on NVD website
To clipboard 

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