Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e219fa0ea95707d…

MALICIOUS

PDF

118.6 KB
MD5: 9bfc1dafa1d76bb693804ea62ce851c1 SHA-1: c03e16d767dbf2743f7edf9c35d59e60d33dd985 SHA-256: 5e219fa0ea95707d9a03d9d39886d2a85503c36f1d42da62d2250e8c0990e028
256 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

This PDF file contains obfuscated JavaScript that utilizes eval() and String.fromCharCode() functions, indicating an attempt to exploit vulnerabilities and execute arbitrary code. The critical heuristic 'PDF_JS_EXPLOIT_CLUSTER' and ClamAV detection 'Pdf.Exploit.Agent-36086' strongly suggest malicious intent. The JavaScript is likely responsible for downloading and executing a secondary payload, a common technique for malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 8

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • 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
91e892a37394da9ee0419a4ab3f9dd8b1206ec4eb8803e619dad5b57ebd94236
pdf-javascript-stream PDF /JS object 6 at offset 0x143 626625 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_001_off0001d6e9.bin
f849b9f32dcc7dc48db086c9a3d397a0102b8ab084f7ca94421ff5e66565167e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1D6E9 300 bytes