Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4506840ae830175…

MALICIOUS

PDF

14.7 KB Created: 2010-10-15 14:23:58 Authoring application: yen vaw
MD5: d851aa543aafcb11bd4e2dda4bd21825 SHA-1: 8a58877a34f52819d4165488e861ccecdf892242 SHA-256: a4506840ae830175c73d5b8d3aa94c005493ae06cf20cc17fe6e8137031e6571
268 Risk Score

Malware Insights

MITRE ATT&CK
T1204 Malicious Link T1059.001 PowerShell

The PDF file contains XFA form elements with embedded JavaScript, triggering a heap spray exploit. This exploit is designed to download and execute a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of an embedded file further supports the payload delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • 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.
  • XFA JavaScript heap-spray exploit code critical PDF_XFA_HEAP_SPRAY
    PDF contains XFA script content with heap-spray or shellcode-like JavaScript markers such as large encoded word sequences, util.pack, large arrays, or spray variable names. This is a weaponised Adobe Reader exploit pattern, not a normal interactive form.
  • ClamAV: Win.Exploit.JS-296 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Win.Exploit.JS-296
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits
  • 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
  • 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.
  • 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://www.xfa.org/schema/xfa-template/2.5/

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0002.bin
d81baa73e490e4cb879e13927cacd1dd1be37524a37eac51603e15117c578777
pdf-embedded-file PDF EmbeddedFile object 2 at offset 0xD91 84 bytes
embedded_file_obj0008.bin
24c130f03a4cf51d470b536e94c1e58af67665739e200e0ce198ad41086243c0
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xE42 228 bytes
embedded_file_obj0019.bin
c97e0522381d6196cc0695f35f4d065f15c9c86a9601a7f776c6afd3f4c6b460
pdf-embedded-file PDF EmbeddedFile object 19 at offset 0xF33 199 bytes
embedded_file_obj0010.bin
31f5aedad71f58cdda2662f0e242f75cc76ccd54d8d2c6562dedfe420c434e1e
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x1024 119 bytes
embedded_file_obj0018.bin
e6c26a3478346d27e841ad49868ebf68bf4c6863b6750e8d60bda3c4c6f79876
pdf-embedded-file PDF EmbeddedFile object 18 at offset 0x10DB 77 bytes
embedded_file_obj0015.bin
92a3ce61d783e15932b5de127ce45a9b4c2f98f4da2453f65241573c1dda808a
pdf-embedded-file PDF EmbeddedFile object 15 at offset 0x1182 56 bytes
embedded_file_obj0001.bin
8b6da22a01277fcb7f1e143444a95c544c043af0008a7437994a9c6cbbc46fa1
pdf-embedded-file PDF EmbeddedFile object 1 at offset 0x14B6 9136 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 6 long base64-like blob(s).