Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b7b80f451560ba1…

MALICIOUS

PDF

15.7 KB
MD5: 320cd7ac3120f9eb9a76dac9af6a47e0 SHA-1: 502450a1743d9f90c8f9cb5b7a6f937ac8b477ee SHA-256: 2b7b80f451560ba1be7b2b17c4dbe6e550ee33cee2faa3cc1b70e1b7e183d1ee
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript/Python T1204.002 Malicious File

The PDF file contains embedded JavaScript, including a large comment-padded eval stager, indicating an attempt to obfuscate and execute malicious code. The presence of eval() and String.fromCharCode() functions further supports this. ClamAV detected this file as 'Pdf.Exploit.Agent-36086', suggesting it's a known exploit. The primary attack pattern involves leveraging a PDF vulnerability to run this script.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • 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_obj0006_000.js
fe2c1b7c49a55e00e77f673a5b943147e870547df18ed1af55e9013191602efa
pdf-javascript-stream PDF /JS object 6 at offset 0x143 424083 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).