Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccdff823295f5ddb…

MALICIOUS

PDF

118.6 KB
MD5: b04faa5cabf802d37ac47827a03f3d56 SHA-1: 6c867828528d641818b6f2a2c71f1c2497334db1 SHA-256: ccdff823295f5ddb8ea5d4eb9d6673e1e3414faeeccc641d6aa2e785e24bca7e
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded JavaScript, which is heavily obfuscated and utilizes eval() and String.fromCharCode. Heuristics indicate a large comment-padded JavaScript eval stager, suggesting it's designed to download and execute a second-stage payload. ClamAV detection confirms its malicious nature, identifying it as Pdf.Exploit.Agent-36086. The lack of specific indicators for a known family leads to an 'unknown family' classification.

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
f9dc14bace7c1edad28d2933049aa2a20d28cd704c5a38979bac6800e11d036d
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626551 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).