Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0948bb6665b87f4…

MALICIOUS

PDF

15.8 KB
MD5: 410da42bb32e8aa22d6211d045feab67 SHA-1: 0f176af1c6da93e678b1bee8b964eb1e5b769d40 SHA-256: f0948bb6665b87f439b1f2cdc73b72a45e37c8866849a0712728247fc56799b5
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1059.007 JavaScript

The PDF contains embedded JavaScript with multiple high-severity heuristic firings, including `PDF_EVAL` and `PDF_JS_LARGE_COMMENT_PADDED_EVAL`. The embedded JavaScript stream, named `javascript_obj0006_000.js`, is heavily obfuscated and likely serves as a stager to download and execute a second-stage payload. The ClamAV detection `Pdf.Exploit.Agent-36086` further confirms its malicious nature.

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
5a3ba22cfb6015bb46f9cc7c1f921cae7941eb8d49d8ad419beb1f20e8fc979a
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425220 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).