Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc317b588314d35f…

MALICIOUS

PDF

37.7 KB
MD5: e37d2ff1f5106bba5302de6fb149d4ac SHA-1: 089ee86402ea92c3a3b5dd6ad84fb9ab33b0bbe2 SHA-256: fc317b588314d35f51fbbcc098268c1cf5237770be525d79fd0e41f4743a11ca
126 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a Flash object, indicated by heuristics like PDF_JAVASCRIPT, PDF_JS, and PDF_RICHMEDIA. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript file, 'javascript_obj0006_000.js', is likely responsible for executing malicious actions, such as downloading and executing a second-stage payload. The presence of these elements suggests a multi-stage attack leveraging embedded content.

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 0xAD5 55839 bytes
javascript_obj0006_000.js
f17664c38f2585907f410b1e8cf021988d80a796164e17754f4a23415e309bb5
pdf-javascript-stream PDF /JS object 6 at offset 0xF5 1582 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).