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CVE-2026-55011

Full vulnerability record from the local CVENow database.

Description

Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally.

Severity
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-14 17:17:08.990000
Last modified
2026-10-24 21:10:00.130000
View original CVE JSON
{
  "id": "CVE-2026-55011",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-14T17:17:08.990",
  "lastModified": "2026-10-24T21:10:00.130",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally."
    },
    {
      "lang": "es",
      "value": "Subdesbordamiento de enteros (ajuste circular o envoltura) en Microsoft Defender permite a un atacante no autorizado ejecutar código localmente."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Microsoft",
          "product": "Microsoft Malware Protection Engine",
          "versions": [
            {
              "version": "1.1.0.0",
              "lessThan": "1.1.26060.3008",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-13T00:00:00+00:00",
          "id": "CVE-2026-55011",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-191"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "1.1.26060.3008",
              "matchCriteriaId": "68C13D1D-69E8-431B-B716-B307ED19733C"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55011",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}