Element is a Matrix web client built using the Matrix React SDK. Versions of Element Web and Desktop earlier than 1.11.85 do not check if thumbnails for attachments, stickers and images are coherent. It is possible to add thumbnails to events trigger a file download once clicked. Fixed in element-web 1.11.85.
The user interface (UI) does not properly represent critical information to the user, allowing the information - or its source - to be obscured or spoofed. This is often a component in phishing attacks.
If an attacker can cause the UI to display erroneous data, or to otherwise convince the user to display information that appears to come from a trusted source, then the attacker could trick the user into performing the wrong action. This is often a component in phishing attacks, but other kinds of problems exist. For example, if the UI is used to monitor the security state of a system or network, then omitting or obscuring an important indicator could prevent the user from detecting and reacting to a security-critical event. UI misrepresentation can take many forms: