Malicious PDF — malware analysis report

Static analysis result for SHA-256 87f2f16f9a7f7ede…

MALICIOUS

PDF

9.3 KB
MD5: 325194dda81f0e5e1ed4789836eab9fd SHA-1: ba550b5fbc582617be11a4c431358eba21c3efde SHA-256: 87f2f16f9a7f7ede35fe60dd3c360f258197aa95c934f70e986ed5e0e329ce28
156 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, indicated by the PDF_EMBEDDED_SCRIPT_PAYLOAD and PDF_XFA_SCRIPT heuristics. The ML classifier strongly flags this PDF as malicious. The deobfuscated.js file was extracted, suggesting the script is designed to download and execute a second-stage payload. The presence of eval() and String.fromCharCode() calls further supports the malicious intent.

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
9ba8c467d83fa956044ceac8c94d086ecd4b977bb430311ec7a8d8376eda643c
pdf-embedded-file PDF EmbeddedFile object 41 at offset 0x52 1160 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
deobfuscated.js
f6f01dfa01b669c72d68610aeadb36272073cb73dff69885774f7ee90cfa8c15
deobfuscated-js PDF JavaScript deobfuscation pass 1645 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).