Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52d0562e0205fdf…

MALICIOUS

PDF

20.6 KB Created: 2010-08-31 11:37:40 Authoring application: aalDual dualGym
MD5: 34f90411657497b8ca071fc389bcf2aa SHA-1: 8461dced7b19b446fcbcd7b7f91cf190f37724ca SHA-256: a52d0562e0205fdf93cb745fcaa2521e6ee5f1c7d821e70ecb035d8ab7670079
168 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.001 Spearphishing Attachment

The PDF sample contains XFA form elements with embedded JavaScript that triggers a heap spray exploit. This exploit is designed to execute arbitrary code, as indicated by the 'PDF_XFA_HEAP_SPRAY' and 'PDF_XFA_SCRIPT' heuristic firings. The embedded file 'embedded_file_obj0010.bin' is likely the secondary payload. The ML classifier strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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.

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
d81baa73e490e4cb879e13927cacd1dd1be37524a37eac51603e15117c578777
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0x142C 84 bytes
embedded_file_obj0009.bin
24c130f03a4cf51d470b536e94c1e58af67665739e200e0ce198ad41086243c0
pdf-embedded-file PDF EmbeddedFile object 9 at offset 0x14DD 228 bytes
embedded_file_obj0010.bin
8bd2d6007efc9e4c79504aa21015ca875e091b5cf6063ac322687a96d3bb09d4
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x15D0 29307 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
embedded_file_obj0011.bin
c97e0522381d6196cc0695f35f4d065f15c9c86a9601a7f776c6afd3f4c6b460
pdf-embedded-file PDF EmbeddedFile object 11 at offset 0x4A0B 199 bytes
embedded_file_obj0012.bin
daf3d9aaeb9f09deb816504ba2061d877f53ce7d1622cea29a94ff81752a4950
pdf-embedded-file PDF EmbeddedFile object 12 at offset 0x4AFD 131 bytes
embedded_file_obj0013.bin
e6c26a3478346d27e841ad49868ebf68bf4c6863b6750e8d60bda3c4c6f79876
pdf-embedded-file PDF EmbeddedFile object 13 at offset 0x4BBE 77 bytes
embedded_file_obj0014.bin
92a3ce61d783e15932b5de127ce45a9b4c2f98f4da2453f65241573c1dda808a
pdf-embedded-file PDF EmbeddedFile object 14 at offset 0x4C65 56 bytes