CVE-2021-32728
mediumpriority · track · 26EPSS 0.009 · 58 %ileEURUUSEPSS · scored 2026-10-28
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
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affected products (8)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (14)
External citations — patches, advisories, analysis.
- https://github.com/nextcloud/desktop/pull/3338cnnvd
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5cnnvd
- https://hackerone.com/reports/1189162cnnvd
- https://vigilance.fr/vulnerability/Nextcloud-Desktop-Client-weak-chiffrement-via-API-Endpoint-Public-Key-36456cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.3145cnnvd
- https://www.debian.org/security/2021/dsa-4974cnnvd
- https://github.com/nextcloud/desktop/pull/3338enisa_euvd
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5enisa_euvd
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