Malicious PDF — malware analysis report

Static analysis result for SHA-256 2121522124de3ab5…

MALICIOUS

PDF

37.7 KB
MD5: 0bae6232bd25a12423491a0caa919999 SHA-1: a3dde116fe2c0b91583910e52c140b9da2021d18 SHA-256: 2121522124de3ab5f103cd10b5387a9aa1700f1d9b42107ded6d766094ad347e
124 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF contains embedded JavaScript and a RichMedia (Flash) object, strongly indicating a malicious intent. The ML classifier output of 0.999988 further supports this. The embedded JavaScript file, 'javascript_obj0006_000.js', is likely responsible for executing the malicious payload, possibly by exploiting a vulnerability within the PDF reader or delivering a secondary stage. The presence of ASCIIHexDecode filter with exploit indicators also points towards exploitation.

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 0xAAD 55839 bytes
javascript_obj0006_000.js
703a49c2f56ae59ad24117bf7e1ff84f0d559c2fa732d2d792ff9299c7ed367e
pdf-javascript-stream PDF /JS object 6 at offset 0xF5 1552 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).