Vulnerability from bitnami_vulndb
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.
{
"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": "2026-09-08T08:34:36.952Z",
"published": "2026-07-12T23:47:43.538Z",
"references": [
{
"type": "ADVISORY",
"url": "https://github.com/nextcloud/android/pull/8438"
},
{
"type": "ADVISORY",
"url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
},
{
"type": "ADVISORY",
"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"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- 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.
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