Add this to your HTML: <script src="http://gist.githubusercontent.com/marckohlbrugge/a265a0532a9d95aa7329/raw/2908baf7d4002cfa9203044d4f5ed6957a282eb5/suchboris.js"></script>

suchboris.js

var imgs = document.getElementsByTagName("img");
for(var i=0, l=imgs.length; i<l; i++) {
imgs[i].src = "http://cdn1.tnwcdn.com/wp-content/themes/icetea/assets/images/column/boris.jpg";
console.log('test');
}