Vulnerability-Lookup

FKIE_CVE-2026-79610

Vulnerability from fkie_nvd - Published: 2026-10-13 16:17 - Updated: 2026-10-13 17:17

Severity

Summary

XSA-501 was about issues with v1 -> v2 and v2 -> v1 changes racing certain other grant table operations. Sadly a v2 -> v1 -> v2 change has yet another effect which wasn't accounted for: During the first change, status pages would be freed. During the second change they would be allocated again. Hence across the full pair of change the addresses of the status pages may change, rendering stale previously calculated pointers into the status array.

References

	URL	Tags
	security@xen.org	https://xenbits.xenproject.org/xsa/advisory-517.html
	af854a3a-2127-422b-91ae-364da2661108	http://www.openwall.com/lists/oss-security/2026/10/13/6
	af854a3a-2127-422b-91ae-364da2661108	http://xenbits.xen.org/xsa/advisory-517.html

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-517"
            }
          ]
        }
      ],
      "source": "security@xen.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "XSA-501 was about issues with v1 -\u003e v2 and v2 -\u003e v1 changes racing certain\nother grant table operations.  Sadly a v2 -\u003e v1 -\u003e v2 change has yet\nanother effect which wasn\u0027t 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."
    }
  ],
  "id": "CVE-2026-79610",
  "lastModified": "2026-10-13T17:17:46.940",
  "metrics": {},
  "published": "2026-10-13T16:17:23.247",
  "references": [
    {
      "source": "security@xen.org",
      "url": "https://xenbits.xenproject.org/xsa/advisory-517.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.openwall.com/lists/oss-security/2026/10/13/6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://xenbits.xen.org/xsa/advisory-517.html"
    }
  ],
  "sourceIdentifier": "security@xen.org",
  "vulnStatus": "Received"
}

CVE-2026-79610 (GCVE-0-2026-79610)

Vulnerability from cvelistv5 – Published: 2026-10-13 15:44 – Updated: 2026-10-13 16:13

Title

grant-table: double version change race

Summary

Severity

No CVSS data available.

Assigner

XEN CNA under the mitre root

CNA scorecard D 56/100 over 46 records in the last 180 days details

References

3 references

URL	Tags
https://xenbits.xenproject.org/xsa/advisory-517.html
http://xenbits.xen.org/xsa/advisory-517.html
http://www.openwall.com/lists/oss-security/2026/10/13/6

Impacted products

1 product

Vendor	Product	Version
Xen	Xen	Unknown: consult Xen advisory XSA-517

Date Public

2026-10-13 12:00

Credits

This issue was discovered by Claude Opus and diagnosed as a security issue by Teddy Astie of Vates.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-10-13T16:13:47.749Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://xenbits.xen.org/xsa/advisory-517.html"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/10/13/6"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "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."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "This issue was discovered by Claude Opus and diagnosed as a security issue\nby Teddy Astie of Vates."
        }
      ],
      "datePublic": "2026-10-13T12:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "XSA-501 was about issues with v1 -\u003e v2 and v2 -\u003e v1 changes racing certain\nother grant table operations.  Sadly a v2 -\u003e v1 -\u003e v2 change has yet\nanother effect which wasn\u0027t 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."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-13T15:44:42.370Z",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN"
      },
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-517.html"
        }
      ],
      "title": "grant-table: double version change race",
      "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."
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "cveId": "CVE-2026-79610",
    "datePublished": "2026-10-13T15:44:42.370Z",
    "dateReserved": "2026-08-25T07:35:05.290Z",
    "dateUpdated": "2026-10-13T16:13:47.749Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted