Malicious PDF — malware analysis report

Static analysis result for SHA-256 f90f5b8ff7511a33…

MALICIOUS

PDF

2.1 KB
MD5: 8b752035d786d27ede596eefeea94685 SHA-1: e07da395b75cbe8ade35acba357ee5e5bdafb0fb SHA-256: f90f5b8ff7511a33756cf6ca462b2b5a4476b06a2ae699c26b35614be69f9c89
106 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes `eval()` and `unescape()` functions, indicating obfuscation. The `String.fromCharCode` heuristic further suggests dynamic code generation. These techniques are commonly used to download and execute further malicious content. While no specific URLs were extracted, the presence of obfuscated JavaScript and the 'Suspicious extracted artifact' heuristic strongly suggest a downloader or exploit delivery mechanism.

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 0x734 332 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).