FKIE_CVE-2026-42493

Vulnerability from fkie_nvd - Published: 2026-07-28 13:18 - Updated: 2026-07-28 17:16
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Addressing certain issues, in particular related to operations which may take excessively long and therefore would need preemption, has turned out overly costly. Since alternatives (HVM/PVH: HAP, PV: shim) are commonly available, the decision was to deprecate the functionality, while still retaining it for people to use at their own (security) risk. Memory-wise small enough guests may still be okay to run.
References
security@xen.orghttps://xenbits.xenproject.org/xsa/advisory-495.html
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/07/28/12
af854a3a-2127-422b-91ae-364da2661108http://xenbits.xen.org/xsa/advisory-495.html
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-495"
            }
          ]
        }
      ],
      "source": "security@xen.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Addressing certain issues, in particular related to operations which may\ntake excessively long and therefore would need preemption, has turned out\noverly costly.  Since alternatives (HVM/PVH: HAP, PV: shim) are commonly\navailable, the decision was to deprecate the functionality, while still\nretaining it for people to use at their own (security) risk.  Memory-wise\nsmall enough guests may still be okay to run."
    }
  ],
  "id": "CVE-2026-42493",
  "lastModified": "2026-07-28T17:16:39.063",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-42493",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-28T15:58:19.075241Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-28T13:18:32.247",
  "references": [
    {
      "source": "security@xen.org",
      "url": "https://xenbits.xenproject.org/xsa/advisory-495.html"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://www.openwall.com/lists/oss-security/2026/07/28/12"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "http://xenbits.xen.org/xsa/advisory-495.html"
    }
  ],
  "sourceIdentifier": "security@xen.org",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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