Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b2cdf5dc4ea0ef…

MALICIOUS

PDF

4.7 KB Created: 2011-04-05 23:46:28 Authoring application: bub lob
MD5: 0d04a9e38ce74f412dd13c6504631139 SHA-1: 2c6ab5266e46233e65f409dc854ab81f1e3c41eb SHA-256: 37b2cdf5dc4ea0effa42f52452fe67bbcb1d193b1d98cd6ba0a4a69c6ac594b1
68 Risk Score

Malware Insights

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

The PDF contains embedded script content, indicated by the 'PDF_EMBEDDED_SCRIPT_PAYLOAD' heuristic. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript file, 'stream_001_off00000329.js', is the primary artifact suggesting the attack vector. While the exact script functionality is not detailed, its presence within a malicious PDF strongly implies it's used to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off00000329.js
6ed2c1722daa43a54496c3d16ca73e2d390b26bbce6732c935ad8055fcbe3e93
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x329 12465 bytes