Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ed7325a7f452840…

MALICIOUS

PDF

4.5 KB Authoring application: Vabameuaki
MD5: f05988e73772705e9b3e9a54c9e2a5cf SHA-1: fcd8fd518b9980c8b1c05017ab927d7eeb37f65c SHA-256: 6ed7325a7f4528406407a2cfce8d25a66eb0913369481a010f1b9e1a3bbdb8b5
86 Risk Score

Malware Insights

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

The PDF contains obfuscated JavaScript that decodes and executes a URL. The script reconstructs the URL "http://evil.tld/payload.exe" which is likely the second-stage payload. The ML classifier and heuristics strongly indicate malicious intent.

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_obj0011_000.js
1ec398366107a5fedd9bcf18a57f32d68d58e87986c8ad1c876f457b209e2152
pdf-javascript-stream PDF /JS object 11 at offset 0xCA2 815 bytes