Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5e0739cea8dee76…

MALICIOUS

PDF

1.9 KB
MD5: 71d7e7bc723f0cb08b7b7cbcf1dc9e20 SHA-1: 7092b5bea0fc330e1ffba1d784afa5273e5786bd SHA-256: d5e0739cea8dee7677a8cbc794d5fb6f15800840ad5e970e92b0a11e3c0dce5e
188 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 Command and Scripting Interpreter: PowerShell T1204.002 Malicious File: Malicious File

The PDF file was flagged by multiple high-severity heuristics, including PDF_EVAL and PDF_UNESCAPE, indicating the presence of obfuscated JavaScript. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript, particularly the deobfuscated version, likely contains code to download and execute a secondary payload, a common technique for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Exploit.Agent-35930 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35930
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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.
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
f23e505f155bfa9b9f356fa9fddf8d7fcafcc37fc2df3878e575e72c00c819d4
pdf-javascript-stream PDF /JS object 111611 at offset 0x670 697 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
840d63fba30f23c66f42d72f351bc05aa29989731ed55783ea031fe1f44935e5
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2834 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).