Malicious PDF — malware analysis report

Static analysis result for SHA-256 31df2fe1db253834…

MALICIOUS

PDF

4.8 KB Created: 2011-04-05 23:46:28 Authoring application: bufdfob
MD5: d60b3e09261ccb9bff47fcd17eb1a40a SHA-1: 4bd345807f843919af086c3ab44d02b137938063 SHA-256: 31df2fe1db2538340f67e39df71373ddffcc06c22d1a4f82619f721149c49fc7
68 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier as malicious with a high confidence score. Static analysis revealed an embedded JavaScript payload within a PDF stream. This script is likely responsible for executing the malicious functionality of the document, potentially downloading and running further payloads.

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_off00000309.js
8f7d2564e25489345696424784d5d4bf43600b88f937669a2564b6eb244be98b
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x309 13251 bytes