Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4f82154b9e8f6c5…

MALICIOUS

PDF

4.1 KB
MD5: c13f71ea34298181852d35fe8ab84d10 SHA-1: 6abf71950cee84389767b44ac812b121b1474558 SHA-256: f4f82154b9e8f6c5573d4157639a30fa574db6baa571d2d0acaf4c9e433e6e68
62 Risk Score

Malware Insights

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

The PDF file contains an embedded JavaScript payload, indicated by the 'PDF_EMBEDDED_SCRIPT_PAYLOAD' heuristic and the presence of 'stream_000_off00000285.js'. The ML classifier strongly flagged this PDF as malicious. The XFA form suggests a complex document structure often used to hide malicious content. The embedded script is likely responsible for downloading and executing a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • 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: PDFException. 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_000_off00000285.js
a00cccf1d3a88135ed2146064f66659f81bf262214183adf6bbcfe04e2cd91bc
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x285 10738 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 long base64-like blob(s).