PoD: Don't try to reclaim special pages

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-62434",
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "dateUpdated": "2026-07-28T13:34:16.161Z",
    "dateReserved": "2026-07-14T10:28:12.655Z",
    "datePublished": "2026-07-28T12:33:08.540Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN",
        "dateUpdated": "2026-07-28T12:33:08.540Z"
      },
      "datePublic": "2026-07-28T12:00:00.000Z",
      "title": "PoD: Don't try to reclaim special pages",
      "descriptions": [
        {
          "lang": "en",
          "value": "A guest started with Populated on Demand enabled (PoD) can attempt to\nreclaim pages which aren't regular guest RAM.  This can cause corruption\nof memory management state in Xen."
        }
      ],
      "affected": [
        {
          "vendor": "Xen",
          "product": "Xen",
          "defaultStatus": "unknown",
          "versions": [
            {
              "version": "consult Xen advisory XSA-507",
              "status": "unknown"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-507.html"
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "A buggy or malicious guest can cause corruption of Xen's state, leading\nto crashes or other malfunctions.  Information leak and privilege\nescalation cannot be ruled out."
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All Xen versions from 3.4 onwards are vulnerable.  Xen versions 3.3 and\nearlier are not vulnerable.\n\nOnly x86 systems are vulnerable.\n\nOnly x86 HVM and PVH guests started in populate-on-demand mode are\nbelieved to be able to leverage the vulnerability.  Populate-on-demand\nmode is activated when the guest's xl configuration file specifies a\n\"maxmem\" value which is larger than the \"memory\" value."
        }
      ],
      "workarounds": [
        {
          "lang": "en",
          "value": "Running only PV guests or HVM/PVH guests without PoD will avoid the\nvulnerability."
        }
      ]
    },
    "adp": [
      {
        "providerMetadata": {
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE",
          "dateUpdated": "2026-07-28T13:34:16.161Z"
        },
        "title": "CVE Program Container",
        "references": [
          {
            "url": "http://xenbits.xen.org/xsa/advisory-507.html"
          }
        ]
      }
    ]
  }
}