Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-07-12 23:47

Modified

2026-07-13 00:08

Summary

End-to-end encryption device setup did not verify public key

Details

Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account.

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "nextcloud",
        "purl": "pkg:bitnami/nextcloud"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.16.1"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-32727"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:android:*:*"
    ],
    "severity": "High"
  },
  "details": "Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account.",
  "id": "BIT-nextcloud-2021-32727",
  "modified": "2026-07-13T00:08:34.851Z",
  "published": "2026-07-12T23:47:43.538Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nextcloud/android/pull/8438"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/1189162"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32727"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "End-to-end encryption device setup did not verify public key"
}

CVE-2021-32727 (GCVE-0-2021-32727)

Vulnerability from cvelistv5 – Published: 2021-07-12 20:40 – Updated: 2024-08-03 23:33

Title

End-to-end encryption device setup did not verify public key

Summary

Severity

5.7 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N

CWE

CWE-295 - Improper Certificate Validation

Assigner

GitHub_M

References

4 references

URL	Tags
https://github.com/nextcloud/security-advisories/…	x_refsource_CONFIRM
https://github.com/nextcloud/android/pull/8438	x_refsource_MISC
https://hackerone.com/reports/1189162	x_refsource_MISC
https://github.com/nextcloud/end_to_end_encryptio…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
nextcloud	security-advisories	Affected: < 3.16.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T23:33:54.870Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/nextcloud/android/pull/8438"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://hackerone.com/reports/1189162"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "security-advisories",
          "vendor": "nextcloud",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.16.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-295",
              "description": "CWE-295: Improper Certificate Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-07-12T20:40:13.000Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/nextcloud/android/pull/8438"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://hackerone.com/reports/1189162"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
        }
      ],
      "source": {
        "advisory": "GHSA-5v33-r9cm-7736",
        "discovery": "UNKNOWN"
      },
      "title": "End-to-end encryption device setup did not verify public key",
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security-advisories@github.com",
          "ID": "CVE-2021-32727",
          "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 3.16.1"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "nextcloud"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account."
            }
          ]
        },
        "impact": {
          "cvss": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736",
              "refsource": "CONFIRM",
              "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736"
            },
            {
              "name": "https://github.com/nextcloud/android/pull/8438",
              "refsource": "MISC",
              "url": "https://github.com/nextcloud/android/pull/8438"
            },
            {
              "name": "https://hackerone.com/reports/1189162",
              "refsource": "MISC",
              "url": "https://hackerone.com/reports/1189162"
            },
            {
              "name": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices",
              "refsource": "MISC",
              "url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
            }
          ]
        },
        "source": {
          "advisory": "GHSA-5v33-r9cm-7736",
          "discovery": "UNKNOWN"
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2021-32727",
    "datePublished": "2021-07-12T20:40:13.000Z",
    "dateReserved": "2021-05-12T00:00:00.000Z",
    "dateUpdated": "2024-08-03T23:33:54.870Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

Vulnerability from bitnami_vulndb

CVE-2021-32727 (GCVE-0-2021-32727)

Tags

Sightings

Nomenclature