Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5dc14d110ee3f54…

MALICIOUS

PDF

118.5 KB
MD5: 36640940b815a5adf6b0c63b9ce11be0 SHA-1: 49e6135471c9b366ac5799fa3a98678f5c1632c0 SHA-256: f5dc14d110ee3f54b525e9a0d12c4d3f8082e1693e8242bd955fd0085a3cbf48
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a large comment-padded eval stager. This JavaScript is obfuscated and uses eval() and String.fromCharCode(), indicating it is designed to execute arbitrary code. The ClamAV detection 'Pdf.Exploit.Agent-36086' further supports that this is a malicious PDF exploiting a known vulnerability. The primary function appears to be the execution of a malicious script, likely for downloading and executing a second-stage payload.

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
7ff0be1c84bc55c82d305639c5b86827795661aee809227a7008b73e138d4a03
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626905 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).