I have a asp.net 3.5 site with a *.asmx that serves several webservice methods. The only client that should be calling these methods is one I wrote, and it calls them using a POST request. However, my error logs show many InvalidOperationException errors due to these methods being called with a GET request.
Question: What might be causing these GET requests? Might proxies convert POST requests to GET requests without the client making the request knowing about it?
to expand on rusanu’s answer, bots and crawlers and/or hackers?