Nextcloud Server is a self hosted personal cloud system. After receiving a "Files drop" or "Password protected" share link a malicious user was able to download attachments that are referenced in Text files without providing the password. It is recommended that the Nextcloud Server is upgraded to 28.0.11, 29.0.8 or 30.0.1 and Nextcloud Enterprise Server is upgraded to 25.0.13.13, 26.0.13.9, 27.1.11.9, 28.0.11, 29.0.8 or 30.0.1.
https://hackerone.com/reports/2376900
https://github.com/nextcloud/text/pull/6485
https://github.com/nextcloud/text/commit/ca24b25c93b81626b4e457c260243edeab5f1548
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-gxph-5m4j-pfmj