Headline
CVE-2023-39952: Advanced permissions not respected when copying entire group folders
Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 22.0.0 and prior to versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1, a user can access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder. Nextcloud Server versions 25.0.8, 26.0.3, and 27.0.1 and Nextcloud Enterprise Server versions 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, and 27.0.1 contain a patch for this issue. No known workarounds are available.
Package
Server (Nextcloud)
Affected versions
>= 25.0.0, >= 26.0.0, >= 27.0.0
Patched versions
25.0.8, 26.0.3, 27.0.1
Server (Nextcloud Enterprise)
>= 22.0.0, >= 23.0.0, >= 24.0.0, >= 25.0.0, >= 26.0.0, >= 27.0.0
22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3, 27.0.1
Description
Impact
A user can access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder.
Patches
It is recommended that the Nextcloud Server is upgraded to 25.0.8, 26.0.3 or 27.0.1
It is recommended that the Nextcloud Enterprise Server is upgraded to 22.2.10.13, 23.0.12.8, 24.0.12.4, 25.0.8, 26.0.3 or 27.0.1
Workarounds
- No workaround available
References
- HackerOne
- PullRequest
- Public issue
For more information
If you have any questions or comments about this advisory:
- Create a post in nextcloud/security-advisories
- Customers: Open a support ticket at portal.nextcloud.com