Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1adce94cf4c731f…

MALICIOUS

PDF

118.6 KB
MD5: e1dc1bccea98e36f055f1c927c876181 SHA-1: a00c942af0975a57113ed75eb27d2f4399edc993 SHA-256: e1adce94cf4c731f9f038a2f4e79decb07c1a3b9904115c2096df163d03d7bb5
196 Risk Score

Malware Insights

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

This PDF contains embedded JavaScript, flagged by multiple heuristics including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_EVAL'. The 'PDF_JS_LARGE_COMMENT_PADDED_EVAL' heuristic specifically indicates a stager pattern. ClamAV detection 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The ML classifier also strongly indicates maliciousness. The primary attack pattern involves exploiting PDF vulnerabilities to run obfuscated JavaScript, which is likely used to download and execute additional malware.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
4bb1e6e31ece61f24049e1105bc1d490f3ccb39f07485109afe997e8df3ecd09
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627006 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).
stream_002_off0001d877.bin
8ba091dd2cdbbefdf8b6b1a4ce166c42b438f60bb4ae5a7c52b3b8727965a3d3
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1D877 200 bytes