Malicious PDF — malware analysis report

Static analysis result for SHA-256 b279fddc535777f8…

MALICIOUS

PDF

29.1 KB Created: 2010-08-29 16:19:36 Authoring application: styeZek colSnap
MD5: 1acec123688e83b035467010c2fd3b6a SHA-1: e8f66e5e40b13e5b736a2735bd663db8c11c6104 SHA-256: b279fddc535777f827cfb40a29f8eda23790de131e7ffa1cd87c4f4e69b54a39
208 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File T1566.002 Spearphishing Attachment

The sample is a PDF file identified as malicious by ClamAV (Pdf.Exploit.Dropped-81) and a machine learning classifier. High-severity heuristics indicate the presence of XFA forms with risky executable scripts and eval() calls. These elements suggest the PDF is designed to exploit vulnerabilities, likely to download and execute a second-stage payload from an embedded URL or artifact. No specific malware family was identified.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • 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.
  • ClamAV: Pdf.Exploit.Dropped-81 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-81
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution
  • 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://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.5/
    • http://ns.adobe.com/xtd/
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://ns.adobe.com/xfdf/
    • http://www.xfa.org/schema/xfa-form/2.8/

Extracted artifacts 8

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
04462f810d6eacdacecc9d0a5f3f81bebc722af4415e04da19b520338f642b51
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xD7 67 bytes
embedded_file_obj0009.bin
e2e0f6c5cb2e0b2697da89386bfc3718eedaf1b6a2b1d24dd1176d27117bf77a
pdf-embedded-file PDF EmbeddedFile object 9 at offset 0x162 781 bytes
embedded_file_obj0010.bin
76e71e452338d7384967dbf3b8d5c06bea128714940cb02957dd801959b08deb
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x4BA 87 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0011.bin
75053d8f07005eae9d7b1dbe1f281e102c5f44ba81b781240effd8c347b35007
pdf-embedded-file PDF EmbeddedFile object 11 at offset 0x55C 26721 bytes
embedded_file_obj0012.bin
103d1e7983cf88bfacedddb4af33ffb5317d9c2c8b3e1bfd987b2c5d712bc985
pdf-embedded-file PDF EmbeddedFile object 12 at offset 0x6E08 323 bytes
embedded_file_obj0014.bin
9035511eba39b5ffb4bdec81b45c98867875af195e374d460662ede3e9237621
pdf-embedded-file PDF EmbeddedFile object 14 at offset 0x6F95 163 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0015.bin
e6c26a3478346d27e841ad49868ebf68bf4c6863b6750e8d60bda3c4c6f79876
pdf-embedded-file PDF EmbeddedFile object 15 at offset 0x707E 77 bytes
embedded_file_obj0016.bin
78b09463af5cd373870eae2e3e83de87b7f6b659e0d0117ab4c09d90ebb2ad95
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0x7112 68 bytes