Malicious PDF — malware analysis report

Static analysis result for SHA-256 b69d0a0155deff65…

MALICIOUS

PDF

4.9 KB Created: 2011-04-05 23:46:28 Authoring application: bub lob
MD5: 27e92b2a3b4d7f24b02f67feeeb67719 SHA-1: 2ec17c66d0c9fef31b20cb4694dc8cffb28ff78c SHA-256: b69d0a0155deff65f6d8edd8e1636781309bde0e5f227e7a4f566b1766610027
70 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier with high confidence. It contains an embedded JavaScript payload, identified as 'stream_001_off00000331.js'. This script is likely responsible for downloading and executing a secondary malicious file, which is a common technique for initial access and further infection. The presence of an embedded script payload and the ML classification strongly indicate malicious intent.

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_off00000331.js
339d8c0f54ff42197cd315525757ebce80afbabd10bd2d1b81736cec0812b6cb
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x331 13529 bytes