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GSD-2021-32728

Vulnerability from gsd - Updated: 2023-12-13 01:23
Details
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.
Aliases
Aliases

{
  "GSD": {
    "alias": "CVE-2021-32728",
    "description": "The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.",
    "id": "GSD-2021-32728",
    "references": [
      "https://www.suse.com/security/cve/CVE-2021-32728.html",
      "https://www.debian.org/security/2021/dsa-4974",
      "https://advisories.mageia.org/CVE-2021-32728.html"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2021-32728"
      ],
      "details": "The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.",
      "id": "GSD-2021-32728",
      "modified": "2023-12-13T01:23:09.009944Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "security-advisories@github.com",
        "ID": "CVE-2021-32728",
        "STATE": "PUBLIC",
        "TITLE": "End-to-end encryption device setup did not verify public key"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "security-advisories",
                    "version": {
                      "version_data": [
                        {
                          "version_value": "\u003c 3.3.0"
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "nextcloud"
            }
          ]
        }
      },
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
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          {
            "lang": "eng",
            "value": "The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading."
          }
        ]
      },
      "impact": {
        "cvss": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        }
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "CWE-295: Improper Certificate Validation"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://hackerone.com/reports/1189162",
            "refsource": "MISC",
            "url": "https://hackerone.com/reports/1189162"
          },
          {
            "name": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5",
            "refsource": "CONFIRM",
            "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5"
          },
          {
            "name": "https://github.com/nextcloud/desktop/pull/3338",
            "refsource": "MISC",
            "url": "https://github.com/nextcloud/desktop/pull/3338"
          },
          {
            "name": "DSA-4974",
            "refsource": "DEBIAN",
            "url": "https://www.debian.org/security/2021/dsa-4974"
          }
        ]
      },
      "source": {
        "advisory": "GHSA-f5fr-5gcv-6cc5",
        "discovery": "UNKNOWN"
      }
    },
    "nvd.nist.gov": {
      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:a:nextcloud:desktop:*:*:*:*:*:*:*:*",
                "cpe_name": [],
                "versionEndExcluding": "3.3.0",
                "vulnerable": true
              }
            ],
            "operator": "OR"
          },
          {
            "children": [],
            "cpe_match": [
              {
                "cpe23Uri": "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              },
              {
                "cpe23Uri": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
                "cpe_name": [],
                "vulnerable": true
              }
            ],
            "operator": "OR"
          }
        ]
      },
      "cve": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2021-32728"
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "en",
              "value": "The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "en",
                  "value": "CWE-295"
                }
              ]
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          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5",
              "refsource": "CONFIRM",
              "tags": [
                "Exploit",
                "Third Party Advisory"
              ],
              "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5"
            },
            {
              "name": "https://github.com/nextcloud/desktop/pull/3338",
              "refsource": "MISC",
              "tags": [
                "Patch",
                "Third Party Advisory"
              ],
              "url": "https://github.com/nextcloud/desktop/pull/3338"
            },
            {
              "name": "https://hackerone.com/reports/1189162",
              "refsource": "MISC",
              "tags": [
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                "Third Party Advisory"
              ],
              "url": "https://hackerone.com/reports/1189162"
            },
            {
              "name": "DSA-4974",
              "refsource": "DEBIAN",
              "tags": [
                "Third Party Advisory"
              ],
              "url": "https://www.debian.org/security/2021/dsa-4974"
            }
          ]
        }
      },
      "impact": {
        "baseMetricV2": {
          "acInsufInfo": false,
          "cvssV2": {
            "accessComplexity": "LOW",
            "accessVector": "NETWORK",
            "authentication": "SINGLE",
            "availabilityImpact": "NONE",
            "baseScore": 4.0,
            "confidentialityImpact": "PARTIAL",
            "integrityImpact": "NONE",
            "vectorString": "AV:N/AC:L/Au:S/C:P/I:N/A:N",
            "version": "2.0"
          },
          "exploitabilityScore": 8.0,
          "impactScore": 2.9,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
          "obtainUserPrivilege": false,
          "severity": "MEDIUM",
          "userInteractionRequired": false
        },
        "baseMetricV3": {
          "cvssV3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "exploitabilityScore": 2.8,
          "impactScore": 3.6
        }
      },
      "lastModifiedDate": "2022-10-04T14:14Z",
      "publishedDate": "2021-08-18T16:15Z"
    }
  }
}



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