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FKIE_CVE-2021-26564

Vulnerability from fkie_nvd - Published: 2021-02-26 22:15 - Updated: 2026-06-17 03:43
Severity
8.3 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
8.7 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Summary
Cleartext transmission of sensitive information vulnerability in synorelayd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to spoof servers via an HTTP session.
References
security@synology.comhttps://www.synology.com/security/advisory/Synology_SA_20_26Vendor Advisory
security@synology.comhttps://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1160Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.synology.com/security/advisory/Synology_SA_20_26Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1160Exploit, Third Party Advisory
Impacted products
Vendor Product Version
synology diskstation_manager *
synology vs960hd_firmware -
synology vs960hd -
synology skynas_firmware -
synology skynas -
synology diskstation_manager_unified_controller 3.0
synology uc3200 -
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Synology DiskStation Manager (DSM)",
          "vendor": "Synology",
          "versions": [
            {
              "lessThan": "6.2.3-25426-3",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@synology.com"
    }
  ],
  "configurations": [
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              "matchCriteriaId": "1628C07C-CCA7-463C-AA98-BF86C97B0D58",
              "versionEndExcluding": "6.2.3-25426-3",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    },
    {
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            }
          ],
          "negate": false,
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        },
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            }
          ],
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      ],
      "operator": "AND"
    },
    {
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          ],
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  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Cleartext transmission of sensitive information vulnerability in synorelayd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to spoof servers via an HTTP session."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de transmisi\u00f3n de informaci\u00f3n confidencial en texto sin cifrar en synorelayd en Synology DiskStation Manager (DSM) versiones anteriores a 6.2.3-25426-3, permite a atacantes de tipo man-in-the-middle falsificar servidores por medio de una sesi\u00f3n HTTP"
    }
  ],
  "id": "CVE-2021-26564",
  "lastModified": "2026-06-17T03:43:29.163",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 5.8,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 4.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.3,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 6.0,
        "source": "security@synology.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N",
          "version": "3.1"
        },
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        "impactScore": 5.8,
        "source": "nvd@nist.gov",
        "type": "Primary"
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  },
  "published": "2021-02-26T22:15:20.300",
  "references": [
    {
      "source": "security@synology.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.synology.com/security/advisory/Synology_SA_20_26"
    },
    {
      "source": "security@synology.com",
      "tags": [
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        "Third Party Advisory"
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      "url": "https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1160"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
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    },
    {
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      "url": "https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1160"
    }
  ],
  "sourceIdentifier": "security@synology.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-319"
        }
      ],
      "source": "security@synology.com",
      "type": "Secondary"
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    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-319"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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