Malicious PDF — malware analysis report

Static analysis result for SHA-256 12621fd236a3409f…

MALICIOUS

PDF

6.4 KB
MD5: e001e9c33a4bf5e0c485bee8c55cc5ac SHA-1: f8152deccab9d158a2674bfd74f62aaf0b12fa6c SHA-256: 12621fd236a3409f13de2cd042f97e9c47bce355e86e3eb629945a371690b9e0
156 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes eval() and String.fromCharCode() functions, indicating an attempt to obfuscate malicious code. This JavaScript is likely responsible for exploiting a known PDF vulnerability to download and execute a secondary payload. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of an exploit attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • 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.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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. (matched inside decoded stream)
  • 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. (matched inside decoded stream)
  • 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)
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
objstm_0024_00.bin
e55dd44f9a2243f941eaaa2807e5db90118f8d3793c4179827569fc8751fc952		 pdf-objstm-decoded PDF /ObjStm 24 0 obj (inflated) 599 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.