In what conditions can WinSCP (and other tools) bypass the scponly login for a user?

[JulianRendell]

Hi -

(tried searching, but search is down right now?)

I'm setting up a remote access via SCP/SFTP.

Looking at the docs (https://www.ixsystems.com/documentation/freenas/11.3-U3.1/services.html?highlight=sftp#ssh) there is a statement:

"Some utilities like WinSCP and Filezilla can bypass the scponly shell."

I've done some Google searching and can't find any information regarding this.

Does anyone have any details regarding what the bypass is? Does it allow remote command execution?

Thanks in advance!