by Kastro
Paper/Archive/CVE-2026-23556

CVE-2026-23556

Xen oxenstored — oxenstored keeps quota related use counts across domain destruction

EPSS 0.1%CVSS 9.4
critical.is priorityof 100
29
CVSS 9.4 (CNA)9.4 / 10 × 3028.2Not in CISA KEV+300.0EPSS percentile 3.1.031 × 200.6No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

When oxenstored is tearing a domain down, the node data is cleaned up but the usage counts are leaked. When the domain ID is eventually reused, the new domain can create fewer nodes before beeing deemed to be over quota.

Affected

ProductAffectedFixed inSource
oxenstoredall–CNA

Scores by source

XEN (CNA)9.4CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refxenbits.xen.org/xsa/advisory-483.htmlrefopenwall.com/lists/oss-security/2026/04/28/10refxenbits.xen.org/xsa/advisory-483.html