Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f5fe4e7b78ac701…

MALICIOUS

PDF

105.5 KB
MD5: b04656a430fcb08dcbbddcc47ac3ead8 SHA-1: 0e4e504df9c2645567a02a986cccd6ec1e86d6fa SHA-256: 2f5fe4e7b78ac701e2115bbb38b194a814614bd5027b056c9898adc2614d9382
168 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1027 Obfuscated Files or Information T1059.007 JavaScript/JScript

This PDF file was flagged as malicious by an ML classifier with high confidence. Static analysis revealed several indicators of malicious intent, including the use of unescape() calls, ASCIIHexDecode filters, and embedded script payloads within XFA forms. An embedded file, 'embedded_file_obj0008.bin', was also detected, suggesting a multi-stage attack. The presence of risky executable scripts in the XFA form indicates the PDF is likely attempting to download and execute a second-stage payload.

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.
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (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.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
d1afd7cb63a5c125d8cbf308e89aa346c77c394e707122f1ae12db4bf975b01e
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xE2 15322 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).