Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca429ecfd79d0aec…

MALICIOUS

PDF

12.1 KB
MD5: 09061188e6831c9f909e80e4bc75b71f SHA-1: 48dca0ba2609dae77e0bf3331b27dc910c635347 SHA-256: ca429ecfd79d0aec337248d4c0753602523c8442e745ecba282645e1380e8133
128 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV with the signature 'Pdf.Exploit.Dropped-90'. Static analysis indicated the presence of an embedded file and the use of ASCIIHexDecode filters, which are common in exploit-laden PDFs. The ML classifier also strongly indicated maliciousness. The exact nature of the exploit and payload is not detailed, but the overall pattern suggests a delivery mechanism for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • ClamAV: Pdf.Exploit.Dropped-90 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-90
  • 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
  • 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: PSSyntaxError. 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
embedded_file_obj0001.bin
6e9f7247305f339386f6ceb9e8066e7189a9c3b48d24ef65d53438f5f9d363f3
pdf-embedded-file PDF EmbeddedFile object 1 at offset 0x5A 1890 bytes