Malicious PDF — malware analysis report

Static analysis result for SHA-256 263686fb6a5d05a1…

MALICIOUS

PDF

4.9 KB Created: 2011-04-05 23:46:28 Authoring application: bub lob
MD5: c068f0979c952e9e22dbd4a890ea4762 SHA-1: 3a63454380ac347a9776eea7d0359eecdc8dbe6f SHA-256: 263686fb6a5d05a1e31170c5a6977b52dbf68c9801f27cd1f6567992b7bd1e6d
66 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 very high confidence score. Static analysis revealed an embedded JavaScript payload within a PDF stream. This script is the primary indicator of malicious activity, likely serving as a downloader or exploit loader. The presence of an embedded file and XFA form are secondary indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • 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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off00000331.js
3ec238f3fbf11b30d70bd67ef489d3d3577911f905082f47f46533196003c54e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x331 13521 bytes