Malicious PDF — malware analysis report

Static analysis result for SHA-256 41b8ad233d2dd1e0…

MALICIOUS

PDF

1.6 KB
MD5: d1d32cdad6f781ca2cccb460325d2964 SHA-1: 918aecbc136213eb11d38e2053af31b27e5f8db4 SHA-256: 41b8ad233d2dd1e0866eaac4bf08fe209eda47323c62f31df6d7825b32c190e8
126 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_EVAL. The presence of `eval()` and `String.fromCharCode` suggests obfuscated code designed to execute malicious actions. The extracted artifact `javascript_obj0009_000.js` is likely responsible for downloading and executing a second-stage payload. The ClamAV detection further confirms its malicious nature.

Heuristics 6

  • ClamAV: Heuristics.PDF.ObfuscatedNameObject critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Heuristics.PDF.ObfuscatedNameObject
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (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_obj0009_000.js
33432dd51c0124a31fd2f0c9212057d773e0cb023be57ff0fc7ba7311df59330
pdf-javascript-stream PDF /JS object 9 at offset 0xDC 3898 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).