Headline
CVE-2021-32734: File path disclosure of shared files in Nextcloud Text application
Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.011, and 21.0.3, the Nextcloud Text application shipped with Nextcloud Server returned verbatim exception messages to the user. This could result in a full path disclosure on shared files. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, one may disable the Nextcloud Text application in Nextcloud Server app settings.
Impact
The Nextcloud Text application shipped with Nextcloud server did return verbatim exception messages to the user. This could result in a full path disclosure on shared files. (e.g. an attacker could see that the file shared.txt is located within /files/$username/Myfolder/Mysubfolder/shared.txt)
Patches
It is recommended that the Nextcloud Server is upgraded to 19.0.13, 20.0.11 or 21.0.3
Workarounds
Disable the Nextcloud Text application in the app settings.
References
- HackerOne
- Pull Request
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 support.nextcloud.com
Related news
Gentoo Linux Security Advisory 202208-17 - Multiple vulnerabilities have been found in Nextcloud, the worst of which could result in denial of service. Versions less than 23.0.4 are affected.