Nextcloud · Nextcloud Server · CVE-2023-39952
**Name of the Vulnerable Software and Affected Versions**
Nextcloud Server versions 22.0.0 through 22.2.10.12
Nextcloud Server versions 23.0.0 through 23.0.12.7
Nextcloud Server versions 24.0.0 through 24.0.12.3
Nextcloud Server versions 25.0.0 through 25.0.7
Nextcloud Server versions 26.0.0 through 26.0.2
**Description**
The issue is related to incorrect access control in Nextcloud Server, allowing a user to access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder. This can enable a remote attacker to gain unauthorized access to protected information.
**Recommendations**
For Nextcloud Server versions 22.0.0 through 22.2.10.12, update to version 22.2.10.13 or later.
For Nextcloud Server versions 23.0.0 through 23.0.12.7, update to version 23.0.12.8 or later.
For Nextcloud Server versions 24.0.0 through 24.0.12.3, update to version 24.0.12.4 or later.
For Nextcloud Server versions 25.0.0 through 25.0.7, update to version 25.0.8 or later.
For Nextcloud Server versions 26.0.0 through 26.0.2, update to version 26.0.3 or later.