Malicious PDF — malware analysis report

Static analysis result for SHA-256 2312fb6fb970439e…

MALICIOUS

PDF

144.1 KB
MD5: b09cff64ab4361837cb1e10d7949e6e9 SHA-1: 142cf038e96537e4548ab4b494cf6dad4ef145c2 SHA-256: 2312fb6fb970439eb05f736360c84c076c5f3d98973cefaf52f9b88d51cb1624
176 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_UNESCAPE. A machine learning classifier and ClamAV detection strongly suggest malicious intent, specifically identifying it as Pdf.Exploit.Agent-36189. The embedded JavaScript is likely responsible for exploiting vulnerabilities within the PDF reader and downloading a second-stage payload from one of the suspicious URLs. The presence of XFA form elements also warrants attention.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • ClamAV: Pdf.Exploit.Agent-36189 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36189
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.bitstream.com
    • http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/2.6/
    • http://www.xfa.org/schema/xfa-template/2.6/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_000.js
b61568091942febbc9af13fc6bb48d0d3f369a8ff241dcdb7ddf657906ba1ac6
pdf-javascript-stream PDF /JS object 13 at offset 0x10531 26581 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
font_00_sfnt_off00000352.bin
a8f4d9b7d604c3c8a0bf3f9a31b9e952d467f98d118fdc784d95d689a14d8a33
pdf-font-stream PDF embedded font (sfnt) at offset 0x352 65932 bytes