{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2023-46835",
        "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "state": "PUBLISHED",
        "assignerShortName": "XEN",
        "dateReserved": "2023-10-27T07:55:35.331Z",
        "datePublished": "2024-01-05T16:34:49.531Z",
        "dateUpdated": "2025-11-04T19:25:41.611Z"
    },
    "containers": {
        "cna": {
            "title": "x86/AMD: mismatch in IOMMU quarantine page table levels",
            "datePublic": "2023-11-14T12:00:00.000Z",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "The current setup of the quarantine page tables assumes that the\nquarantine domain (dom_io) has been initialized with an address width\nof DEFAULT_DOMAIN_ADDRESS_WIDTH (48) and hence 4 page table levels.\n\nHowever dom_io being a PV domain gets the AMD-Vi IOMMU page tables\nlevels based on the maximum (hot pluggable) RAM address, and hence on\nsystems with no RAM above the 512GB mark only 3 page-table levels are\nconfigured in the IOMMU.\n\nOn systems without RAM above the 512GB boundary\namd_iommu_quarantine_init() will setup page tables for the scratch\npage with 4 levels, while the IOMMU will be configured to use 3 levels\nonly, resulting in the last page table directory (PDE) effectively\nbecoming a page table entry (PTE), and hence a device in quarantine\nmode gaining write access to the page destined to be a PDE.\n\nDue to this page table level mismatch, the sink page the device gets\nread/write access to is no longer cleared between device assignment,\npossibly leading to data leaks.\n"
                }
            ],
            "impacts": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "A device in quarantine mode can access data from previous quarantine\npage table usages, possibly leaking data used by previous domains that\nalso had the device assigned.\n"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "defaultStatus": "unknown",
                    "product": "Xen",
                    "vendor": "Xen",
                    "versions": [
                        {
                            "status": "unknown",
                            "version": "consult Xen advisory XSA-445"
                        }
                    ]
                }
            ],
            "configurations": [
                {
                    "lang": "en",
                    "value": "All Xen versions supporting PCI passthrough are affected.\n\nOnly x86 AMD systems with IOMMU hardware are vulnerable.\n\nOnly x86 guests which have physical devices passed through to them can\nleverage the vulnerability.\n"
                }
            ],
            "workarounds": [
                {
                    "lang": "en",
                    "value": "Not passing through physical devices to guests will avoid the\nvulnerability.\n\nNot using quarantine scratch-page mode will avoid the vulnerability,\nbut could result in other issues.\n"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "This issue was discovered by Roger Pau Monné of XenServer.\n"
                }
            ],
            "references": [
                {
                    "url": "https://xenbits.xenproject.org/xsa/advisory-445.html"
                }
            ],
            "providerMetadata": {
                "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
                "shortName": "XEN",
                "dateUpdated": "2024-01-05T16:34:49.531Z"
            }
        },
        "adp": [
            {
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://xenbits.xenproject.org/xsa/advisory-445.html",
                        "tags": [
                            "x_transferred"
                        ]
                    },
                    {
                        "url": "http://xenbits.xen.org/xsa/advisory-445.html"
                    }
                ],
                "providerMetadata": {
                    "orgId": "af854a3a-2127-422b-91ae-364da2661108",
                    "shortName": "CVE",
                    "dateUpdated": "2025-11-04T19:25:41.611Z"
                }
            },
            {
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "type": "CWE",
                                "cweId": "CWE-787",
                                "lang": "en",
                                "description": "CWE-787 Out-of-bounds Write"
                            }
                        ]
                    }
                ],
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 5.5,
                            "attackVector": "LOCAL",
                            "baseSeverity": "MEDIUM",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
                            "integrityImpact": "NONE",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "NONE",
                            "privilegesRequired": "LOW",
                            "confidentialityImpact": "HIGH"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2024-04-12T04:00:28.791183Z",
                                "id": "CVE-2023-46835",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-06-17T16:11:08.422Z"
                }
            }
        ]
    }
}