Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8a0a161b99fcba5…

MALICIOUS

PDF

146.9 KB
MD5: d85aa40f914fcaeddc86c61fa6e7f351 SHA-1: 3de4ccb3e36a89a2c685ef2152d63f464426250b SHA-256: c8a0a161b99fcba5ceb206853018dfd2a850f6fd0df3d835bbbc4046e68475ab
176 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV (Pdf.Exploit.Agent-36189) and a machine learning classifier. It contains embedded JavaScript streams which are obfuscated and utilize unescape() calls, indicating an attempt to hide malicious code. The presence of XFA forms and JavaScript actions suggests an exploit targeting PDF vulnerabilities. The primary IOCs are the embedded URLs and the ClamAV detection name.

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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_000.js
3defe957ad49d8ab792f3a324ca6f996be13e3da8fc20a1f27a3875ec5e1b0df
pdf-javascript-stream PDF /JS object 13 at offset 0x10531 27541 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).
javascript_obj0013_001.js
fc170f4677e3efaeb7defd7ab34ba29928c2e885a4f9d11387d68108b3ebf27e
pdf-javascript-stream PDF /JS object 13 at offset 0x1056D 27549 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