CVE-2026-23555
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.1 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- EPSS
- 0.18% probability · 8th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-617
- Affected
- xen/xen
- Source
- security@xen.org
References
- https://xenbits.xenproject.org/xsa/advisory-481.htmlPatch, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2026/03/17/7Mailing List, Patch, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-481.htmlPatch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.