Flask-AppBuilder is an application development framework, built on top of Flask. Prior to version 4.3.2, an authenticated malicious actor with Admin privileges, could by adding a special character on the add, edit User forms trigger a database error, this error is surfaced back to this actor on the UI. On certain database engines this error can include the entire user row including the pbkdf2:sha256 hashed password. This vulnerability has been fixed in version 4.3.2.
https://github.com/dpgaspar/Flask-AppBuilder/security/advisories/GHSA-jhpr-j7cq-3jp3
https://github.com/dpgaspar/Flask-AppBuilder/releases/tag/v4.3.2
https://github.com/dpgaspar/Flask-AppBuilder/pull/2045
https://github.com/dpgaspar/Flask-AppBuilder/commit/ae25ad4c87a9051ebe4a4e8f02aee73232642626