A vulnerability was found in Nextcloud Circle up to 0.19.14/0.20.10/0.21.3 (Cloud Software). It has been classified as problematic. Affected is an unknown code of the component Secret Circle. Upgrading to version 0.19.15, 0.20.11 or 0.21.4 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.