I left Charles (web proxy debugger) running and waited for the re-direct again. I found the site that is originating the request to sponsor.adverstitial.com, it is ad.cpmaxads.com.
A request to that site goes out, then it brings back a lot of shady looking javascript/HTML mix with this in the middle:
{var v=Math.floor((Math.random()*100000));setTimeout(function(){try{window.top.location.href="http://sponsor.adverstitial.com/view/advertisement?loc="+v+"&adv="+p+"&camp="+o+"&w="+t+"&h="+B+"&rnd=4878995824626992114"}catch(d){}},2000)}}
The request to ad.cpmaxads.com from the web page was:
GET /audience/campaign?adid=2832800&cpid=657304&w=728&h=90&rn=1397433511&ct=http://clk.specificclick.net/click/v=5%3Bm=3%3Bl=12679%3Bc=657304%3Bb=2832800%3Bts=20140413195831%3Bui=9BHmMkGDmpd5VsqEQpYbPNeNVqvOhgeY_JYZTk4np7i31BriQpt2BAVz7vpcD5rKAI1kfLriLvqflWaNGuBRQA%3Bdct=
And the referring page was from Slashdot.org.
I'm pretty sure now this is specifically an advertisement that manages to force the whole page to load a new URL, as you can kind of make out from the Javascript - so at least it's not malware. I'm going to try setting a /etc/hosts entry as follows to block the origin of the offending Javascript:
0.0.0.0 sponsor.adverstitial.com
0.0.0.0 ad.cpmaxads.com
As it comes from advertising, this probably occurs for any other sites using that advertiser. If people are not comfortable editing /etc/hosts, you could also try installing an ad-blocker, and just blacklisting ad.cpmaxads.com if you didn't want the whole ad-block experience (I don't like how it slows things down and I do want to support sites I like with advertising revenue - as long as ads do not infuriate me be repaving the whole page...)
For those interested in the whole HTML/javascript block that comes back from ad.cpmaxads.com, it is:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta http-equiv="expires" content="0"><meta http-equiv="Pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache">
</head>
<body>
<div id="adarea" style="position:absolute; top:0px; left:0px; width:300px; height:250px;">
<!-- default -->
<!-- end default -->
</div>
<img src="http://s.viewalytics.com/t/e?p=52&t=7&ev=1&asrc=0&site=0&rnd=0" width=1 height=1 border=0 style="position:absolute; top:-4px;">
<script type="text/javascript">
function getParameterByName_fromURL(b,f){try{b=b.replace(/[\[]/,"\\[").replace(/[\]]/,"\\]");var a="[\\?&]"+b+"=([^&#]*)";var d=new RegExp(a);var c=d.exec(f);if(c==null){return""}else{return decodeURIComponent(c[1].replace(/\+/g," "))}}catch(g){return""}}var placement_oo="1";var placement_lo="1";(function(){function H(f,w){try{f=f.replace(/[\[]/,"\\[").replace(/[\]]/,"\\]");var d="[\\?&]"+f+"=([^&#]*)";var r=new RegExp(d);var h=r.exec(w);if(h==null){return""}else{return decodeURIComponent(h[1].replace(/\+/g," "))}}catch(J){return""}}function C(e,d){var f=document.getElementById("adarea");if(f){if((e==728)&(d==90)){f.style.width="728px";f.style.height="90px";f.innerHTML='<iframe width=728 height=90 border="0" frameborder="0" marginwidth="0" marginheight="0" topmargin="0" leftmargin="0" hspace="0" vspace="0" scrolling="NO" src="http://ad.cpmaxads.com/audience/default/default_728_90.html"></iframe>'}else{if((e==300)&(d==250)){f.style.width="300px";f.style.height="250px";f.innerHTML='<iframe width=300 height=250 border="0" frameborder="0" marginwidth="0" marginheight="0" topmargin="0" leftmargin="0" hspace="0" vspace="0" scrolling="NO" src="http://ad.cpmaxads.com/audience/default/default_300_250.html"></iframe>'}else{if((e==120)&(d==600)){f.style.width="120px";f.style.height="600px";f.innerHTML='<a href="http://www.stjude.org/moments?sc_cid=bnn103"><img src="http://ad.cpmaxads.com/audience/default/psa/120x600.gif" width="120" height="600" border="0"></a>'}else{if((e==160)&(d==600)){f.style.width="160px";f.style.height="600px";f.innerHTML='<iframe width=160 height=600 border="0" frameborder="0" marginwidth="0" marginheight="0" topmargin="0" leftmargin="0" hspace="0" vspace="0" scrolling="NO" src="http://ad.cpmaxads.com/audience/default/default_160_600.html"></iframe>'}else{f.style.width="300px";f.style.height="250px";f.innerHTML='<a href="http://www.stjude.org/moments?sc_cid=bnn102"><img src="http://ad.cpmaxads.com/audience/default/psa/300x250.gif" width="300" height="250" border="0"></a>'}}}}}}var p;var o;var t;var B;var l;try{p=H("adid",window.location.href)}catch(D){p=0}try{o=H("cpid",window.location.href)}catch(D){o=0}try{t=H("w",window.location.href)}catch(D){t=0}try{B=H("h",window.location.href)}catch(D){B=0}try{l=H("ct",window.location.href)}catch(D){l=""}C(t,B);function i(r,K,h){var J=new Array();J[0]="0";J[1]="0";J[2]="0";try{var d=r.indexOf(" ",K+h);if(d==-1){d=r.length}var f=r.substring(K+h,d);if(f.indexOf(".")>0){J=f.split(".");if(!J[0]){J[0]="0"}if(!J[1]){J[1]="0"}if(!J[2]){J[2]="0"}}}catch(w){}return J}var G=false;var b=0;var k=0;var c;try{c=navigator.userAgent;if(!c){c="unknown"}c=c.toLowerCase();if(c.indexOf("msie")>0){b=1}else{if(c.indexOf("chrome/")>0){b=2;G=true}else{if(c.indexOf("safari/")>0){b=3;G=true}else{if(c.indexOf("firefox/")>0){b=4;G=true}else{if(c.indexOf("trident/")>0){b=7;G=true}}}}}if(c.indexOf("windows")>0){k=1}else{if(c.indexOf("macintosh")>0){k=2}}}catch(D){}var s=0;try{if(b==1){var q=i(c,c.indexOf("msie"),5);s=Number(q[0]);if((s==8)||(s==9)||(s==10)){G=true}}}catch(D){}function j(){var f;try{if(typeof document.hidden!=="undefined"){f="hidden"}else{if(typeof document.mozHidden!=="undefined"){f="mozHidden"}else{if(typeof document.msHidden!=="undefined"){f="msHidden"}else{if(typeof document.webkitHidden!=="undefined"){f="webkitHidden"}}}}}catch(r){}var e=0;if(f){try{if(typeof document.addEventListener!="undefined"&&typeof f!="undefined"){if(document[f]){e=2}else{e=1}}}catch(h){e=0}}return e}var u="true";var a=j();if(!a){a=0}var m=false;try{var n=document.location.href;var g=document.referrer;if((n.indexOf("delta")>0)&&(n.indexOf(u)>0)){m=true}if((n.indexOf("11526")>0)||(n.indexOf("42823")>0)){m=true}if((g.indexOf("delta")>0)&&(g.indexOf(u)>0)){m=true}if((g.indexOf("11526")>0)||(g.indexOf("42823")>0)){m=true}}catch(E){}if((p>0)&&(o>0)&&(G==true)&&(a!=2)&&(k>0)){if(((t==728)&(B==90))||((t==300)&(B==250))||((t==120)&(B==600))||((t==160)&(B==600))){try{if((window.location.protocol=="http:")&&(m==false)){var v=Math.floor((Math.random()*100000));setTimeout(function(){try{window.top.location.href="http://sponsor.adverstitial.com/view/advertisement?loc="+v+"&adv="+p+"&camp="+o+"&w="+t+"&h="+B+"&rnd=4878995824626992114"}catch(d){}},2000)}}catch(E){}}else{}}else{var y=t;var x=B;if((a==2)&&(placement_oo=="1")){var I="http://ad.cpmaxads.com/audience/default/psa/default.swf?width="+y+"&height="+x+"&rn="+Math.round(Math.random()*100000000);var z=navigator.userAgent.toLowerCase();var A="";if((z)&&(z.indexOf("msie")<0)){A='<object style="position:absolute; top:0px; left:0px; display:block; line-height:0px; margin:0; padding:0;" id="defaulted_banner" name="defaulted_banner" type="application/x-shockwave-flash" data="'+I+'" width="1" height="1"><param name="movie" value="'+I+'"/><param name="quality" value="low"/><param name="bgcolor" value="#808080"/><param name="play" value="true"/><param name="loop" value="false"/><param name="wmode" value="window" /><param name="allowScriptAccess" value="always" /><param name="hasPriority" value="true"/></object>'}else{if(z){A='<object style="position:absolute; top:0px; left:0px; display:block; line-height:0px; margin:0; padding:0;" id="defaulted_banner" name="defaulted_banner" classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" width="1" height="1"><param name="movie" value="'+I+'"/><param name="quality" value="low"/><param name="bgcolor" value="#808080"/><param name="play" value="true"/><param name="loop" value="false"/><param name="wmode" value="window" /><param name="allowScriptAccess" value="always" /><param name="hasPriority" value="true"/></object>'}}if(A){var F=document.createElement("div");F.style.position="absolute";F.style.top="4px";F.style.left="4px";F.style.margin="0";F.style.padding="0";F.style.zIndex=2147483647;F.innerHTML=A;try{document.body.appendChild(F)}catch(E){}}}}})();
</script>
</body>
</html>
Best Answer
Found the next solution: clicked on my avatar, then settings. There was the sacred button "full-version"