{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-23559", "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "state": "PUBLISHED", "assignerShortName": "XEN", "dateReserved": "2026-01-14T13:07:36.961Z", "datePublished": "2026-07-09T15:09:51.762Z", "dateUpdated": "2026-07-09T16:02:32.186Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f", "shortName": "XEN", "dateUpdated": "2026-07-09T15:09:51.762Z" }, "title": "Multiple RBAC issues in XAPI", "datePublic": "2026-04-29T18:05:00.000Z", "problemTypes": [ { "descriptions": [ { "lang": "en", "cweId": "CWE-250", "description": "CWE-250 Execution with unnecessary privileges", "type": "CWE" } ] } ], "impacts": [ { "capecId": "CAPEC-233", "descriptions": [ { "lang": "en", "value": "CAPEC-233 Privilege Escalation" } ] } ], "affected": [ { "vendor": "Xen", "product": "XAPI", "versions": [ { "status": "affected", "version": "all" } ], "defaultStatus": "unaffected" } ], "descriptions": [ { "lang": "en", "value": "[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]\n\n\nXAPI can configure different users with different roles, using Role\nBased Access Control. For more details, see:\n\n https://docs.xenserver.com/en-us/xencenter/current-release/rbac-overview.html#rbac-roles \n\nThe pool-admin role is fully privileged. Notably, users with this role\ncan also SSH into the host as root.\n\nThe other administrator roles are pool-operator, vm-power-admin and\nvm-admin, each of which are authorised to configure and manage various\naspects of the system.\n\nSome settings are inadequately restricted, and can be set by a lower\nprivilege of administrator than expected.\n\n * CVE-2026-23559: A vm-admin can set VBD.other_config:backend-local and\n turn arbitrary files in dom0 into VDIs (virtual disks) and give said\n disks to a VM they control. This is an arbitrary read and/or modify\n of files in dom0.\n\n * CVE-2026-23560: A vm-admin can set VM.other-config:is_system_domain\n and mark a VM as a system domain. System domains are ignored and\n left running during certain other host/pool operations, and may be\n hidden from view in tooling.\n\n * CVE-2026-23561: A vm-admin can set VM.other_config:storage_driver_domain\n and mark a VM as the storage domain for a particular host storage\n connection (PBD). Shutting down the VM can cause the PBD to be\n erroneously marked as unplugged when it is not.\n\n * CVE-2026-23562: Configuration of PCI passthrough is normally\n restricted to the pool-admin role. However one API was missing this\n check, allowing a vm-admin access to unintended host hardware.\n\n * CVE-2026-42486: A vm-admin can set the VM.platform:hvm_serial\n parameter, which should be restricted to the pool-admin role, as it\n can allow arbitrary dom0 file write.", "supportingMedia": [ { "type": "text/html", "base64": false, "value": "[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]
XAPI can configure different users with different roles, using Role\nBased Access Control.  For more details, see:\n\n  https://docs.xenserver.com/en-us/xencenter/current-release/rbac-overview.html#rbac-roles\n\nThe pool-admin role is fully privileged.  Notably, users with this role\ncan also SSH into the host as root.\n\nThe other administrator roles are pool-operator, vm-power-admin and\nvm-admin, each of which are authorised to configure and manage various\naspects of the system.\n\nSome settings are inadequately restricted, and can be set by a lower\nprivilege of administrator than expected.\n\n * CVE-2026-23559: A vm-admin can set VBD.other_config:backend-local and\n   turn arbitrary files in dom0 into VDIs (virtual disks) and give said\n   disks to a VM they control.  This is an arbitrary read and/or modify\n   of files in dom0.\n\n * CVE-2026-23560: A vm-admin can set VM.other-config:is_system_domain\n   and mark a VM as a system domain.  System domains are ignored and\n   left running during certain other host/pool operations, and may be\n   hidden from view in tooling.\n\n * CVE-2026-23561: A vm-admin can set VM.other_config:storage_driver_domain\n   and mark a VM as the storage domain for a particular host storage\n   connection (PBD). Shutting down the VM can cause the PBD to be\n   erroneously marked as unplugged when it is not.\n\n * CVE-2026-23562: Configuration of PCI passthrough is normally\n   restricted to the pool-admin role.  However one API was missing this\n   check, allowing a vm-admin access to unintended host hardware.\n\n * CVE-2026-42486: A vm-admin can set the VM.platform:hvm_serial\n   parameter, which should be restricted to the pool-admin role, as it\n   can allow arbitrary dom0 file write.
" } ] } ], "references": [ { "url": "https://xenbits.xen.org/xsa/advisory-489.html" } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "HIGH", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.4, "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H" } } ], "source": { "discovery": "UNKNOWN" }, "x_generator": { "engine": "Vulnogram 1.0.2" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-07-09T16:02:25.587757Z", "id": "CVE-2026-23559", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-07-09T16:02:32.186Z" } } ] } }