Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f0ec6f6c4580d5…

MALICIOUS

PDF

118.7 KB
MD5: df17d15f485e5c1102955d07161ac6b9 SHA-1: f6a9af29e04c7849105af7c136d78521891a2339 SHA-256: 83f0ec6f6c4580d50e2f0b77e30aa606bac6a888082be24be1f8a38adff01599
196 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a call to eval() and a large comment-padded JavaScript eval stager. ClamAV detected this as 'Pdf.Exploit.Agent-36086', indicating a known exploit. The ML classifier also strongly flagged it as malicious. The embedded JavaScript is highly likely to be responsible for downloading and executing a second-stage payload, which is a common technique for PDF-based malware.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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
a13b52708d8d3670c235ee773a13bd04c8d9a5b184e25c1e6f45c3a5ccd4c1ca
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626471 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).