Malicious PDF — malware analysis report

Static analysis result for SHA-256 778c4f86e73a6a8d…

MALICIOUS

PDF

11.7 KB
MD5: 98817db721d9f1b1168c28936b288f37 SHA-1: 2de32b5b4ba477c132923b7cc0321f43021b13bb SHA-256: 778c4f86e73a6a8db2fdf0c7caaf71adab1d04f5e63421c4f5fb7389d9db3f8c
116 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Exploit.Dropped-78', and an ML classifier indicating a high probability of maliciousness. The presence of an embedded script payload and an embedded file suggests the document is designed to exploit vulnerabilities and download a secondary payload. The benign URLs found do not detract from the malicious indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • ClamAV: Pdf.Exploit.Dropped-78 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-78
  • 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
  • Embedded script payload in PDF stream low 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 URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xfa-template/2.5/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
f4bc2c4025bc58a8c9798e8d7e69c5b62181f293f44b9d9c02d1e03a3b782855
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xC8 11265 bytes