Malicious PDF — malware analysis report

Static analysis result for SHA-256 a100caee84d1a9ea…

MALICIOUS

PDF

118.6 KB
MD5: 94eae77688aee366e0f37cf61fb4f848 SHA-1: f38002dbd8dd5c43ca1d1f8c23937da8ae08056d SHA-256: a100caee84d1a9ea91b4d07128857c3b197be4d52e4bdee76029aecb1887a6ce
166 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, including a large, obfuscated eval stager. This script is designed to download and execute a second-stage payload. The presence of PDF_JAVASCRIPT, PDF_JS, PDF_EVAL, and PDF_FROMCHARCODE heuristics, along with the ClamAV detection of 'Pdf.Exploit.Agent-36086', strongly indicates an exploit or downloader. The extracted artifact 'javascript_obj0006_000.js' is the likely source of the malicious script.

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
ff48fb624093096abe7f6ca19b7d7644a6ffc2cdc89a31e78dac44dae6cb648e
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627161 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).