A CWE-425: Direct Request ('Forced Browsing') vulnerability exists in the Web Server on Modicon M340, Legacy Offers Modicon Quantum and Modicon Premium and associated Communication Modules (see security notification for affected versions), that could cause disclosure of sensitive data when sending a specially crafted request to the controller over HTTP.
https://www.se.com/ww/en/download/document/SEVD-2020-343-03/