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FKIE_CVE-2026-78605

Vulnerability from fkie_nvd - Published: 2026-09-01 20:17 - Updated: 2026-09-02 18:50
Severity
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Summary
Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') (CWE-444) in Elasticsearch can lead to information disclosure via HTTP Request Smuggling (CAPEC-33). Under specific proxy deployment configurations, a network attacker could obtain confidential responses intended for other authenticated users.
References
security@elastic.cohttps://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-141/390092Vendor Advisory
Impacted products
Vendor Product Version
elastic elasticsearch *
elastic elasticsearch *
elastic elasticsearch 9.5.0
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Elasticsearch",
          "vendor": "Elastic",
          "versions": [
            {
              "lessThanOrEqual": "8.19.19",
              "status": "affected",
              "version": "8.18.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "9.4.4",
              "status": "affected",
              "version": "9.0.0",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "9.5.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@elastic.co"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2AB47052-19F5-47F9-A688-3AE9CD1B7629",
              "versionEndExcluding": "8.19.20",
              "versionStartIncluding": "8.18.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "519911BD-5669-440F-9159-89D8167CE961",
              "versionEndExcluding": "9.4.5",
              "versionStartIncluding": "9.0.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:elastic:elasticsearch:9.5.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "39484E9B-30B0-4D11-912D-B07373083EE5",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request Smuggling\u0027) (CWE-444) in Elasticsearch can lead to information disclosure via HTTP Request Smuggling (CAPEC-33). Under specific proxy deployment configurations, a network attacker could obtain confidential responses intended for other authenticated users."
    }
  ],
  "id": "CVE-2026-78605",
  "lastModified": "2026-09-02T18:50:25.313",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "security@elastic.co",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-78605",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-01T19:41:44.021783Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-01T20:17:23.757",
  "references": [
    {
      "source": "security@elastic.co",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-141/390092"
    }
  ],
  "sourceIdentifier": "security@elastic.co",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-444"
        }
      ],
      "source": "security@elastic.co",
      "type": "Secondary"
    }
  ]
}



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