Malicious PDF — malware analysis report

Static analysis result for SHA-256 5594799fdeb55efd…

MALICIOUS

PDF

9.5 KB
MD5: d6f2976c1d662a3aca96fb57512a7db1 SHA-1: cef87191e59968b5de7e4aa72d06e99f54b84819 SHA-256: 5594799fdeb55efd0e3ba7b6570f1015b9549d3dca1528c7a70f3e8d10bff18b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 Scripting: JavaScript T1204.002 Malicious File: Malicious File

The PDF contains XFA forms and embedded JavaScript, indicated by the PDF_XFA and PDF_XFA_SCRIPT heuristics. The ML classifier strongly flags this PDF as malicious. The deobfuscated.js artifact suggests the script's purpose is to download and execute a second-stage payload, which is a common attack vector for malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 7

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • 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
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0041.bin
2340d7cb2f8b4fe5445d49911e33c38d1d24c18197e78d6764153a0e761b3e70
pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x52 1162 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
deobfuscated.js
d98ae174c7755be15c14a27e79ec5870f0bc7aaab1ad87fd45a72008bc807569
deobfuscated-js PDF JavaScript deobfuscation pass 2147 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).