Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba003d4f1d8c2c14…

MALICIOUS

PDF

2.1 KB
MD5: cea0e27c71960d0dd15fc8761aee45f3 SHA-1: 0313d54da83e56edc5294f86df80f3614dcd478d SHA-256: ba003d4f1d8c2c141c043bfe0fb5a824095e7ad122d91b79c98b9c9755542960
106 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.007 JavaScript

The PDF file contains embedded JavaScript, which is heavily obfuscated using eval() and unescape() functions, along with String.fromCharCode. This obfuscated script, found in the javascript_obj111611_000.js artifact, strongly suggests an attempt to download and execute a secondary payload. The high heuristic scores for PDF_EVAL and PDF_UNESCAPE further support this conclusion. Due to the obfuscation, the exact nature of the payload cannot be determined, hence the family is unknown.

Heuristics 6

  • 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.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • 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
javascript_obj111611_000.js
9864171cc4152f5d3e5671809dd40cebe1cf9319d0b8bfb0abd003cff50482db
pdf-javascript-stream PDF /JS object 111611 at offset 0x736 332 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).