TDengine is an open source, time-series database optimized for Internet of Things devices. Prior to 3.4.1.15, a Data Reader admin_user on a TDengine Cloud DB instance could run create udf even though standard users should have read-only permissions for non-database objects and show dnodes and create user were denied. This issue is fixed in version 3.4.1.15.
https://github.com/taosdata/TDengine/security/advisories/GHSA-fmp7-rf4r-8q7p