Malicious PDF — malware analysis report

Static analysis result for SHA-256 03c3ea6d4f681582…

MALICIOUS

PDF

6.3 KB Authoring application: Woibneqeni (via 08ed8Uzenwzijecijawida)
MD5: 60864c7547c3d16536ecc07bd5bffbdb SHA-1: 9cf68fb03f8a52d7c6c488a43ed34c6b96fc067e SHA-256: 03c3ea6d4f681582d958a65b06751434175e81e10c0d496e813d74772db2c543
86 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript that is obfuscated but appears to be a stager. The script reconstructs a string of hexadecimal values, which are then evaluated. This pattern strongly suggests the script is designed to download and execute a second-stage payload from a remote source. The ML classifier and heuristic firings confirm the malicious nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • Page-word XOR JavaScript eval stager high PDF_PAGE_WORD_XOR_EVAL_STAGER
    PDF JavaScript enumerates rendered page words with getPageNthWord/getPageNumWords, extracts encoded byte fragments, XOR-decodes the stage with char-code helpers, and evals the result. This is an old exploit-kit staging pattern and is not normal document JavaScript.
  • JavaScript action low 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_obj0010_000.js
e5fb7241b86520d30618ed164f0373984e043b354e933bd4bfa81c848e06fafc
pdf-javascript-stream PDF /JS object 10 at offset 0x11B0 1464 bytes