CVE-2026-33523

{
  "id": "CVE-2026-33523",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-04T15:16:04.227",
  "lastModified": "2026-10-26T19:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers.\n\nThis issue affects Apache HTTP Server: from through 2.4.66.\n\nUsers are recommended to upgrade to version 2.4.67, which fixes the issue."
    },
    {
      "lang": "es",
      "value": "Vulnerabilidad de división de respuesta HTTP en múltiples módulos del Servidor HTTP Apache con servidores backend no confiables o comprometidos.\n\nEste problema afecta al Servidor HTTP Apache: desde hasta 2.4.66.\n\nSe recomienda a los usuarios actualizar a la versión 2.4.67, la cual corrige el problema."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Apache Software Foundation",
          "product": "Apache HTTP Server",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "2.4.0",
              "lessThanOrEqual": "2.4.66",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "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:L/I:L/A:N",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-04T15:55:00.471385Z",
          "id": "CVE-2026-33523",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-443"
        }
      ]
    },
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "NVD-CWE-Other"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "2.4.0",
              "versionEndExcluding": "2.4.67",
              "matchCriteriaId": "3BEA6923-FB92-4DCC-92A2-D5916CDC58FF"
            }
          ]
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      ]
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  ],
  "references": [
    {
      "url": "https://httpd.apache.org/security/vulnerabilities_24.html",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "http://www.openwall.com/lists/oss-security/2026/05/04/23",
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ]
    }
  ]
}