Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa8ab01d8646fe0c…

MALICIOUS

PDF

15.8 KB
MD5: 698c4e3ec6ec2c0fd860db0bf08e56d7 SHA-1: 8affd0ee48160d9dd1a01faf20d4a4cb60298e0d SHA-256: fa8ab01d8646fe0cdf25e0c0019c1a99034fd6a12a36343d7c22dfa487768120
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, including a large, obfuscated stager that utilizes `eval()` and `String.fromCharCode()`. This script is highly indicative of a downloader or exploit loader. The ClamAV detection `Pdf.Exploit.Agent-36086` further supports the malicious nature of the file. The primary attack pattern involves exploiting PDF vulnerabilities to run arbitrary code, likely leading to the download of additional malware.

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
82f08e4b16b22c0734ecaf2a125556f1737849acac9efd481f1f085599fae164
pdf-javascript-stream PDF /JS object 6 at offset 0x143 426461 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).