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GSD-2021-32656

Vulnerability from gsd - Updated: 2023-12-13 01:23
Details
Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the "Add server automatically once a federated share was created successfully" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable "Add server automatically once a federated share was created successfully" in the Nextcloud settings.
Aliases
Aliases

{
  "GSD": {
    "alias": "CVE-2021-32656",
    "description": "Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the \"Add server automatically once a federated share was created successfully\" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable \"Add server automatically once a federated share was created successfully\" in the Nextcloud settings.",
    "id": "GSD-2021-32656",
    "references": [
      "https://security.archlinux.org/CVE-2021-32656"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-32656"
      ],
      "details": "Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the \"Add server automatically once a federated share was created successfully\" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable \"Add server automatically once a federated share was created successfully\" in the Nextcloud settings.",
      "id": "GSD-2021-32656",
      "modified": "2023-12-13T01:23:09.075661Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
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        "ID": "CVE-2021-32656",
        "STATE": "PUBLIC",
        "TITLE": "Trusted servers exchange can be triggered by attacker"
      },
      "affects": {
        "vendor": {
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            {
              "product": {
                "product_data": [
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                    "product_name": "security-advisories",
                    "version": {
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                          "version_value": "\u003c 19.0.11"
                        },
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                          "version_value": "\u003e= 20.0.0, \u003c 20.0.10"
                        },
                        {
                          "version_value": "\u003e= 21.0.0, \u003c 21.0.2"
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            "value": "Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the \"Add server automatically once a federated share was created successfully\" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable \"Add server automatically once a federated share was created successfully\" in the Nextcloud settings."
          }
        ]
      },
      "impact": {
        "cvss": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 8.6,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N",
          "version": "3.1"
        }
      },
      "problemtype": {
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            "description": [
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                "value": "CWE-284: Improper Access Control"
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      "references": {
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            "name": "GLSA-202208-17",
            "refsource": "GENTOO",
            "url": "https://security.gentoo.org/glsa/202208-17"
          }
        ]
      },
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        "discovery": "UNKNOWN"
      }
    },
    "nvd.nist.gov": {
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        "nodes": [
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            "cpe_match": [
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                "cpe_name": [],
                "versionEndExcluding": "19.0.11",
                "vulnerable": true
              },
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              },
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                "cpe_name": [],
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        "description": {
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              "value": "Nextcloud Server is a Nextcloud package that handles data storage. A vulnerability in federated share exists in versions prior to 19.0.11, 20.0.10, and 21.0.2. An attacker can gain access to basic information about users of a server by accessing a public link that a legitimate server user added as a federated share. This happens because Nextcloud supports sharing registered users with other Nextcloud servers, which can be done automatically when selecting the \"Add server automatically once a federated share was created successfully\" setting. The vulnerability is patched in versions 19.0.11, 20.0.10, and 21.0.2 As a workaround, disable \"Add server automatically once a federated share was created successfully\" in the Nextcloud settings."
            }
          ]
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        "problemtype": {
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        "references": {
          "reference_data": [
            {
              "name": "https://hackerone.com/reports/1167853",
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              "tags": [
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            },
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      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "LOW",
            "accessVector": "NETWORK",
            "authentication": "NONE",
            "availabilityImpact": "NONE",
            "baseScore": 5.0,
            "confidentialityImpact": "PARTIAL",
            "integrityImpact": "NONE",
            "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
            "version": "2.0"
          },
          "exploitabilityScore": 10.0,
          "impactScore": 2.9,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
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            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 8.6,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 3.9,
          "impactScore": 4.0
        }
      },
      "lastModifiedDate": "2022-10-25T15:47Z",
      "publishedDate": "2021-06-01T22:15Z"
    }
  }
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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