Headline
CVE-2023-32320: Brute force protection allows to send more requests than intended
Nextcloud Server is a data storage system for Nextcloud, a self-hosted productivity platform. When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response was sent to the client. This allowed someone to send as many requests the server could handle in parallel to bruteforce protected details instead of the configured limit, default 8. Nextcloud Server versions 25.0.7 and 26.0.2 and Nextcloud Enterprise Server versions 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7 and 26.0.2 contain patches for this issue.
Impact
When multiple requests are sent in parallel, all of them were executed even if the amount of faulty requests succeeded the limit by the time the response is sent to the client. This allowed to send as many requests the server could handle in parallel to bruteforce protected details instead of the configured limit (default 8).
Patches
It is recommended that the Nextcloud Server is upgraded to 25.0.7 or 26.0.2
It is recommended that the Nextcloud Enterprise Server is upgraded to 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7 or 26.0.2
Workarounds
- No workaround available
References
- HackerOne
- PullRequest
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