When copying from untrusted sources, you should always review what you paste.
In bash, you can use C-x C-e to open the current command in an editor,
paste it into the editor (not directly onto the command line), review
it, and then bash will execute what you save and exit (so you save
an empty file to cancel).
Now if you want to disable the warnings, possibly because you trust your sources,
then add this line to the settings.json (source: this superuser question):
"multiLinePasteWarning": false