This is an ad served by Google Ads. It appears superimposed on a (legitimate) web page, with the rest of the page blurred out. I didn't check to see where clicking the Open button would take me, but I doubt it's anywhere good.
Google does allow users to give feedback on this ad, but the only option is "Seen too many times”. There is no option to flag it as the blatant cross-site scripting/probable #phishing attack that it is.