CVE-2026-62428 (GCVE-0-2026-62428)

Vulnerability from cvelistv5 – Published: 2026-07-28 12:32 – Updated: 2026-07-28 16:33
VLAI
Title
grant-table: type confusion in grant-copy
Summary
When grant-copy operations are processed, the respective grant may or may not already be in use by another operation (a mapping or another copy). For all copy operations the referenced guest frame is looked up. When another operation is already active for the grant (the grant is "pinned"), what is being supplied back to actually carry out permission checks and copy operation may not be consistent: The permission check may be carried out on a page different from the one involved in the copy.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-28 15:10 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
References
Impacted products
Vendor Product Version CPE status
Xen Xen Unknown: consult Xen advisory XSA-500
guessed Create a notification for this product.
Date Public
2026-07-28 12:00
Credits
This issue was discovered by Roman S.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-07-28T16:33:28.183Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://xenbits.xen.org/xsa/advisory-500.html"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/07/28/16"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "HIGH",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "CHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-62428",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-28T15:10:28.542416Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-367",
                "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-28T15:10:53.004Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-500"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All Xen versions from 4.2 onwards are vulnerable.  Xen versions 4.1 and\nearlier are not vulnerable.\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."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "This issue was discovered by Roman S."
        }
      ],
      "datePublic": "2026-07-28T12:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "When grant-copy operations are processed, the respective grant may or may\nnot already be in use by another operation (a mapping or another copy).\nFor all copy operations the referenced guest frame is looked up.  When\nanother operation is already active for the grant (the grant is \"pinned\"),\nwhat is being supplied back to actually carry out permission checks and\ncopy operation may not be consistent: The permission check may be carried\nout on a page different from the one involved in the copy."
        }
      ],
      "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."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-28T12:32:07.573Z",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN"
      },
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-500.html"
        }
      ],
      "title": "grant-table: type confusion in grant-copy",
      "workarounds": [
        {
          "lang": "en",
          "value": "There is no known mitigation."
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "cveId": "CVE-2026-62428",
    "datePublished": "2026-07-28T12:32:07.573Z",
    "dateReserved": "2026-07-14T10:28:12.655Z",
    "dateUpdated": "2026-07-28T16:33:28.183Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-62428",
      "date": "2026-09-30",
      "epss": "0.00118",
      "percentile": "0.0156"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unknown",
                "product": "Xen",
                "vendor": "Xen",
                "versions": [
                  {
                    "status": "unknown",
                    "version": "consult Xen advisory XSA-500"
                  }
                ]
              }
            ],
            "source": "security@xen.org"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "When grant-copy operations are processed, the respective grant may or may\nnot already be in use by another operation (a mapping or another copy).\nFor all copy operations the referenced guest frame is looked up.  When\nanother operation is already active for the grant (the grant is \"pinned\"),\nwhat is being supplied back to actually carry out permission checks and\ncopy operation may not be consistent: The permission check may be carried\nout on a page different from the one involved in the copy."
          }
        ],
        "id": "CVE-2026-62428",
        "lastModified": "2026-07-28T17:16:53.687",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "HIGH",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "CHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.1,
              "impactScore": 6.0,
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-62428",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-28T15:10:28.542416Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-07-28T13:19:01.713",
        "references": [
          {
            "source": "security@xen.org",
            "url": "https://xenbits.xenproject.org/xsa/advisory-500.html"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "http://www.openwall.com/lists/oss-security/2026/07/28/16"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "url": "http://xenbits.xen.org/xsa/advisory-500.html"
          }
        ],
        "sourceIdentifier": "security@xen.org",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-367"
              }
            ],
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2026-07-28T18:00:19+00:00",
      "cve": "CVE-2026-62428",
      "id": "CVE-2026-62428",
      "initial_release_date": "2026-07-28T12:32:07.573000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "xen: Xen: Type confusion in grant-copy operations can lead to security bypass",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-62428.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-18T00:49:08Z",
      "cve": "CVE-2026-62428",
      "id": "CVE-2026-62428",
      "initial_release_date": "2026-07-30T16:35:53Z",
      "product_status:known_affected": "462",
      "product_status:recommended": "128",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-62428",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-62428.json",
      "version": "7"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2026-07-28T16:33:28.183Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "url": "http://xenbits.xen.org/xsa/advisory-500.html"
              },
              {
                "url": "http://www.openwall.com/lists/oss-security/2026/07/28/16"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "metrics": [
              {
                "cvssV3_1": {
                  "attackComplexity": "HIGH",
                  "attackVector": "LOCAL",
                  "availabilityImpact": "HIGH",
                  "baseScore": 7.8,
                  "baseSeverity": "HIGH",
                  "confidentialityImpact": "HIGH",
                  "integrityImpact": "HIGH",
                  "privilegesRequired": "LOW",
                  "scope": "CHANGED",
                  "userInteraction": "NONE",
                  "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                  "version": "3.1"
                }
              },
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-62428",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "total"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-07-28T15:10:28.542416Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "problemTypes": [
              {
                "descriptions": [
                  {
                    "cweId": "CWE-367",
                    "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition",
                    "lang": "en",
                    "type": "CWE"
                  }
                ]
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-07-28T15:10:12.429Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unknown",
              "product": "Xen",
              "vendor": "Xen",
              "versions": [
                {
                  "status": "unknown",
                  "version": "consult Xen advisory XSA-500"
                }
              ]
            }
          ],
          "configurations": [
            {
              "lang": "en",
              "value": "All Xen versions from 4.2 onwards are vulnerable.  Xen versions 4.1 and\nearlier are not vulnerable.\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."
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "value": "This issue was discovered by Roman S."
            }
          ],
          "datePublic": "2026-07-28T12:00:00.000Z",
          "descriptions": [
            {
              "lang": "en",
              "value": "When grant-copy operations are processed, the respective grant may or may\nnot already be in use by another operation (a mapping or another copy).\nFor all copy operations the referenced guest frame is looked up.  When\nanother operation is already active for the grant (the grant is \"pinned\"),\nwhat is being supplied back to actually carry out permission checks and\ncopy operation may not be consistent: The permission check may be carried\nout on a page different from the one involved in the copy."
            }
          ],
          "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."
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-07-28T12:32:07.573Z",
            "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
            "shortName": "XEN"
          },
          "references": [
            {
              "url": "https://xenbits.xenproject.org/xsa/advisory-500.html"
            }
          ],
          "title": "grant-table: type confusion in grant-copy",
          "workarounds": [
            {
              "lang": "en",
              "value": "There is no known mitigation."
            }
          ]
        }
      },
      "cveMetadata": {
        "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "assignerShortName": "XEN",
        "cveId": "CVE-2026-62428",
        "datePublished": "2026-07-28T12:32:07.573Z",
        "dateReserved": "2026-07-14T10:28:12.655Z",
        "dateUpdated": "2026-07-28T16:33:28.183Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.