CVE-2021-32656: 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…

PriorityP349high8.6CVSS 3.1

AVNACLPRNUINSCCHINAN

EPSS

1.84%

76.3th percentile

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
nextcloud	nextcloud_server	< 19.0.11	19.0.11
nextcloud	nextcloud_server	>= 20.0.0 < 20.0.10	20.0.10
nextcloud	nextcloud_server	>= 21.0.0 < 21.0.2	21.0.2
nextcloud	security-advisories	< 19.0.11	19.0.11
nextcloud	security-advisories	—	—
nextcloud	security-advisories	—	—

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:P/I:N/A:N

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