Malicious PDF — malware analysis report

Static analysis result for SHA-256 feef44ce0cc50c5e…

MALICIOUS

PDF

5.1 KB Created: 2011-04-05 23:46:28 Authoring application: bgfab
MD5: b6435f2f5751cf0d28b59d86d7a8b148 SHA-1: b5367b5bbaa05c11dc5a2e085959ef3b733bc893 SHA-256: feef44ce0cc50c5e2f6560f343b95b6a04d5968a8a0ce198f5ebde8004a9a776
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 and contains an embedded JavaScript file. The embedded script is highly likely to be a downloader for a second-stage payload. The presence of an embedded script and the ML classification strongly suggest a malicious intent, though the specific family could not be determined.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off00000306.js
39d51802a6d944ff57ca841f41094bb0ee3fde689bec190dec0f1b79210da681
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x306 55391 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).