CVE-2026-23557
Last modified
CVE-2026-23557 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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.. EPSS estimates a 0.16% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | >= 4.2.0 |
References
- https://xenbits.xenproject.org/xsa/advisory-484.htmlPatch, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/04/28/11Mailing List, Patch, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-484.htmlPatch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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