Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7665195ac03588c…

MALICIOUS

PDF

37.7 KB
MD5: ba369af6fca2f6e15eefc3bf396ea779 SHA-1: 7b78f2bbaf9e8b7d66f46793619c7c1ce864790b SHA-256: c7665195ac03588cbb870afdd55109a77b37acae1246b8b1d9a462a2f8846c66
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File T1059.007 JavaScript

The PDF contains embedded JavaScript and Flash content, indicated by the PDF_JAVASCRIPT, PDF_JS, and PDF_RICHMEDIA heuristics. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript file, 'javascript_obj0006_000.js', likely contains obfuscated code designed to download and execute a second-stage payload. The presence of ASCIIHexDecode with exploit indicators further suggests an attempt to conceal malicious code execution.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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
Adobe.swf
ce5f7936cf8e3536a88a804ce2d6902022df1794fa878bdc64a26866e34ba989
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0xAC7 55839 bytes
javascript_obj0006_000.js
384ee4a2a7fbe07399ecbdaeed05cc205e07b67371b1c7f66fa86541a154240a
pdf-javascript-stream PDF /JS object 6 at offset 0xF5 1576 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).