Nextcloud office/richdocuments is an office suit for the nextcloud server platform. In affected versions the Collabora integration can be tricked to provide access to any file without proper permission validation. As a result any user with access to Collabora can obtain the content of other users files. It is recommended that the Nextcloud Office App (Collabora Integration) is updated to 7.0.2 (Nextcloud 25), 6.3.2 (Nextcloud 24), 5.0.10 (Nextcloud 23), 4.2.9 (Nextcloud 21-22), or 3.8.7 (Nextcloud 15-20). There are no known workarounds for this issue.

Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform, and Nextcloud Office is a document collaboration app for the same platform. Nextcloud Server 24.0.x prior to 24.0.8 and 25.0.x prior to 25.0.1, Nextcloud Enterprise Server 24.0.x prior to 24.0.8 and 25.0.x prior to 25.0.1, and Nextcloud Office (Richdocuments) App 6.x prior to 6.3.1 and 7.x prior to 7.0.1 have previews accessible without a watermark. The download should be hidden and the watermark should get applied. This issue is fixed in Nextcloud Server 25.0.1 and 24.0.8, Nextcloud Enterprise Server 25.0.1 and 24.0.8, and Nextcloud Office (Richdocuments) App 7.0.1 (for 25) and 6.3.1 (for 24). No known workarounds are available.

Nextcloud richdocuments is a Nextcloud app integrating the office suit Collabora Online. In affected versions the secure view feature of the rich documents app can be bypassed by using unprotected internal API endpoint of the rich documents app. It is recommended that the Nextcloud Office app (richdocuments) is upgraded to 8.0.0-beta.1, 7.0.2 or 6.3.2. Users unable to upgrade may mitigate the issue by taking steps to restrict the ability to download documents. This includes ensuring that the WOPI configuration is configured to only serve documents between Nextcloud and Collabora. It is highly recommended to define the list of Collabora server IPs as the allow list within the Office admin settings of Nextcloud.