Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b0b5274d7fc801d…

MALICIOUS

PDF

15.7 KB
MD5: 5fa25d3cae11a0133281de4d16d29018 SHA-1: 5ce7374bc7fa1dea1efcd937ca9ab713fc3a5de7 SHA-256: 2b0b5274d7fc801df1519275ce44cab931fde8d1ef0880eeadf46ce70e0c470d
166 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, including a heavily obfuscated 'eval' stager within a large comment. This stager is designed to decode and execute arbitrary code. The presence of 'eval()' and 'String.fromCharCode' strongly suggests the script's purpose is to download and execute a second-stage payload. ClamAV also detected this file as 'Pdf.Exploit.Agent-36086', further confirming 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
101b8d4b4cbd632170ee4e84d9759c93ec30496de7cdd7d59c4010d56b0eefbd
pdf-javascript-stream PDF /JS object 6 at offset 0x143 426427 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).