The shareinfo controller in the ownCloud Server before 10.8.0 allows an attacker to bypass the permission checks for upload only shares and list metadata about the share.
https://owncloud.com/security-advisories/cve-2021-35949/
https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-22584
https://doc.owncloud.com/server/admin_manual/release_notes.html