{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-79610",
        "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "state": "PUBLISHED",
        "assignerShortName": "XEN",
        "dateReserved": "2026-08-25T07:35:05.290Z",
        "datePublished": "2026-10-13T15:44:42.370Z",
        "dateUpdated": "2026-10-20T17:33:21.929Z"
    },
    "containers": {
        "cna": {
            "title": "grant-table: double version change race",
            "datePublic": "2026-10-13T12:00:00.000Z",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "XSA-501 was about issues with v1 -> v2 and v2 -> v1 changes racing certain\nother grant table operations.  Sadly a v2 -> v1 -> v2 change has yet\nanother effect which wasn't accounted for: During the first change, status\npages would be freed.  During the second change they would be allocated\nagain.  Hence across the full pair of change the addresses of the status\npages may change, rendering stale previously calculated pointers into the\nstatus array."
                }
            ],
            "impacts": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "An unprivileged guest may be able to elevate its privileges to that of the\nhost.  Information leaks and Denial of Service (DoS) are possible as well."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "defaultStatus": "unknown",
                    "product": "Xen",
                    "vendor": "Xen",
                    "versions": [
                        {
                            "status": "unknown",
                            "version": "consult Xen advisory XSA-517"
                        }
                    ]
                }
            ],
            "configurations": [
                {
                    "lang": "en",
                    "value": "All Xen versions from 4.0 onwards are vulnerable.  Xen versions 3.4 and\nearlier are not vulnerable.\n\nOnly x86 guests permitted to use grant table version 2 interfaces can\nleverage this vulnerability.  On Arm, grant table v2 use is explicitly\nunsupported.\n\nOnly multi-vCPU guests can leverage this vulnerability.\n\nXen versions 4.13 and newer offer a way to build Xen without grant table\nsupport.  Such hypervisors (CONFIG_GRANT_TABLE turned off) are not\nvulnerable."
                }
            ],
            "workarounds": [
                {
                    "lang": "en",
                    "value": "Using the \"gnttab=max-ver:1\" hypervisor command line option will avoid\nthe vulnerability.\n\nUsing the \"max_grant_version=1\" guest configuration option for guests will\nalso avoid the vulnerability."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "finder",
                    "value": "This issue was discovered by Claude Opus and diagnosed as a security issue\nby Teddy Astie of Vates."
                }
            ],
            "references": [
                {
                    "url": "https://xenbits.xenproject.org/xsa/advisory-517.html"
                }
            ],
            "providerMetadata": {
                "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
                "shortName": "XEN",
                "dateUpdated": "2026-10-13T15:44:42.370Z"
            }
        },
        "adp": [
            {
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "http://xenbits.xen.org/xsa/advisory-517.html"
                    },
                    {
                        "url": "http://www.openwall.com/lists/oss-security/2026/10/13/6"
                    }
                ],
                "providerMetadata": {
                    "orgId": "af854a3a-2127-422b-91ae-364da2661108",
                    "shortName": "CVE",
                    "dateUpdated": "2026-10-13T16:13:47.749Z"
                }
            },
            {
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "type": "CWE",
                                "cweId": "CWE-362",
                                "lang": "en",
                                "description": "CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"
                            }
                        ]
                    }
                ],
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "CHANGED",
                            "version": "3.1",
                            "baseScore": 8.8,
                            "attackVector": "LOCAL",
                            "baseSeverity": "HIGH",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
                            "integrityImpact": "HIGH",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "LOW",
                            "confidentialityImpact": "HIGH"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-10-20T17:33:08.282097Z",
                                "id": "CVE-2026-79610",
                                "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": "2026-10-20T17:33:21.929Z"
                }
            }
        ]
    }
}