Vulnerability-Lookup

CVE-2026-62431 (GCVE-0-2026-62431)

Vulnerability from cvelistv5 – Published: 2026-07-28 12:32 – Updated: 2026-07-28 16:33

Title

Viridian STIMER division by zero

Summary

The logic to handle periodic Viridian STIMERs performs a division with an unchecked user-controlled divisor value, that can be set to zero to cause a #DE fault.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-369 - Divide By Zero

Assigner

XEN

References

3 references

URL	Tags
https://xenbits.xenproject.org/xsa/advisory-504.html
http://xenbits.xen.org/xsa/advisory-504.html
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Xen	Xen	Unknown: consult Xen advisory XSA-504

Date Public

2026-07-28 12:00

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
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        "providerMetadata": {
          "dateUpdated": "2026-07-28T16:33:31.447Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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        "references": [
          {
            "url": "http://xenbits.xen.org/xsa/advisory-504.html"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/07/28/20"
          }
        ],
        "title": "CVE Program Container"
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        "metrics": [
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            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "NONE",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
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                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-28T15:49:03.810668Z",
                "version": "2.0.3"
              },
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        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-369",
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                "type": "CWE"
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        "providerMetadata": {
          "dateUpdated": "2026-07-28T15:49:09.743Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-504"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All Xen versions from 4.13 onwards are vulnerable.  Xen versions 4.12 and\nearlier are not vulnerable.\n\nOnly HVM guests with Viridian STIMERs enabled can trigger the vulnerability."
        }
      ],
      "datePublic": "2026-07-28T12:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "The logic to handle periodic Viridian STIMERs performs a division with an\nunchecked user-controlled divisor value, that can be set to zero to cause a #DE\nfault."
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "Enabling Viridian STIMERs to unprivileged HVM guests can result in a Denial\nof Service (DoS) affecting the entire host."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-28T12:32:43.849Z",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
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      },
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-504.html"
        }
      ],
      "title": "Viridian STIMER division by zero",
      "workarounds": [
        {
          "lang": "en",
          "value": "Not enabling Viridian STIMERs for HVM guests will avoid the vulnerability.\n\nNote Viridian extensions are not enabled by default."
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
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    "datePublished": "2026-07-28T12:32:43.849Z",
    "dateReserved": "2026-07-14T10:28:12.655Z",
    "dateUpdated": "2026-07-28T16:33:31.447Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-62431\",\"sourceIdentifier\":\"security@xen.org\",\"published\":\"2026-07-28T13:19:02.010\",\"lastModified\":\"2026-07-28T17:16:55.977\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"The logic to handle periodic Viridian STIMERs performs a division with an\\nunchecked user-controlled divisor value, that can be set to zero to cause a #DE\\nfault.\"}],\"affected\":[{\"source\":\"security@xen.org\",\"affectedData\":[{\"vendor\":\"Xen\",\"product\":\"Xen\",\"defaultStatus\":\"unknown\",\"versions\":[{\"version\":\"consult Xen advisory XSA-504\",\"status\":\"unknown\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-07-28T15:49:03.810668Z\",\"id\":\"CVE-2026-62431\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-369\"}]}],\"references\":[{\"url\":\"https://xenbits.xenproject.org/xsa/advisory-504.html\",\"source\":\"security@xen.org\"},{\"url\":\"http://www.openwall.com/lists/oss-security/2026/07/28/20\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"},{\"url\":\"http://xenbits.xen.org/xsa/advisory-504.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"}]}}",
    "redhat_vex": {
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      "cve": "CVE-2026-62431",
      "id": "CVE-2026-62431",
      "initial_release_date": "2026-07-28T12:32:43.849000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "xen: Xen: Denial of Service due to division by zero in Viridian STIMER handling",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-62431.json",
      "version": "3"
    },
    "vulnrichment": {
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}

GHSA-248Q-W8JQ-JXJ9

Vulnerability from github – Published: 2026-07-28 15:32 – Updated: 2026-07-28 18:33

Details

The logic to handle periodic Viridian STIMERs performs a division with an unchecked user-controlled divisor value, that can be set to zero to cause a #DE fault.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-62431"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-369"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T13:19:02Z",
    "severity": "HIGH"
  },
  "details": "The logic to handle periodic Viridian STIMERs performs a division with an\nunchecked user-controlled divisor value, that can be set to zero to cause a #DE\nfault.",
  "id": "GHSA-248q-w8jq-jxj9",
  "modified": "2026-07-28T18:33:02Z",
  "published": "2026-07-28T15:32:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-62431"
    },
    {
      "type": "WEB",
      "url": "https://xenbits.xenproject.org/xsa/advisory-504.html"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/28/20"
    },
    {
      "type": "WEB",
      "url": "http://xenbits.xen.org/xsa/advisory-504.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

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.

Detection rules are retrieved from Rulezet.

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.

Action not permitted

CVE-2026-62431 (GCVE-0-2026-62431)

GHSA-248Q-W8JQ-JXJ9

Tags

Sightings

Nomenclature