Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbfc6edfc8e51f73…

MALICIOUS

PDF

5.3 KB
MD5: 8d8968be7bfe65bd281c599ed6e6b6d4 SHA-1: 647c0ff725ed3ce06cc62ab07a5c96db3df8f125 SHA-256: fbfc6edfc8e51f737566c93e47c90b3791ea7bf77c9f67a352ea1cb2049f3692
98 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File T1059.001 PowerShell

The sample is a PDF file exhibiting multiple heuristic firings related to XFA forms and encoded content filters, indicating potential exploitability. A critical finding reveals a secondary embedded PDF with suspicious static findings, suggesting a multi-stage attack. The presence of 'Please, wait...' in the document body implies a lure to keep the user engaged while the exploit executes.

Heuristics 5

  • Secondary embedded PDF body has suspicious static findings critical POLYGLOT_CHILD_PDF_STATIC_TRIAGE
    A valid PDF body was found at a nonzero offset inside another container and its carved contents matched PDF exploit or lure heuristics. This catches polyglots where the top-level magic routes to ZIP/OLE while a PDF reader or downstream parser opens the hidden PDF payload.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • ASCII85Decode filter (with exploit indicators) low PDF_FILTER_85
    ASCII85 encoding filter present alongside exploit delivery indicators — uncommon outside of obfuscation
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PSEOF. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
polyglot_child_pdf_off00001198.pdf
9199c7ab996fd48b8003285dcec16ee000e09e492f35fe4f40f0af8fdf58303d
polyglot-child-pdf Secondary PDF body inside pdf container at offset 0x1198 907 bytes