Malicious PDF — malware analysis report

Static analysis result for SHA-256 7718ae4605eb5d16…

MALICIOUS

PDF

12.0 KB
MD5: 9c5f55a2511144681ae8a63f3f4276b4 SHA-1: af32d5e40ed2b07a7f21ce9f8437a2c2ed8c9165 SHA-256: 7718ae4605eb5d16ee548a656b2dcdc9989565dd9f7c2f8f981592fd2197d3d7
128 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File: User Execution T1566.002 Phishing: Spearphishing Attachment

This PDF file was flagged as malicious by multiple engines, including a high-confidence ML classifier and ClamAV, which identified it as 'Pdf.Exploit.Dropped-90'. The presence of the ASCIIHexDecode filter with exploit indicators and an embedded file suggests it is designed to drop and execute a secondary payload. The XFA form and embedded file further support its role as a delivery mechanism for exploits.

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
28b8c6907f334aebbeb45b8975b708954fef9308fe46967eeaa444c79db5c005
pdf-embedded-file PDF EmbeddedFile object 1 at offset 0x5A 1875 bytes