Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a6d2efcc21c75d7…

MALICIOUS

PDF

19.3 KB Created: 2012-09-17 23:33:20 +04:00 Authoring application: Adobe Acrobat 10.0 (via Acrobat Web Capture 10.0)
MD5: 63796bb1f6251566fe5b38218b4cbe3c SHA-1: e06282b65515df505651e7af26f76adc0b6bf9b0 SHA-256: 0a6d2efcc21c75d728d2044e5ff39501020c2c2794f899e3db8f5d2e257419e9
118 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript that is heavily obfuscated using string concatenation and `fromCharCode`. The ML classifier and heuristics strongly indicate a malicious PDF exploit. The JavaScript is designed to download and execute a secondary payload, as evidenced by the obfuscated string which likely decodes to a URL or executable path. Given the nature of the exploit and the embedded script, the most likely initial access vector is spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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.
  • 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.
  • 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.
  • 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/
    • http://www.iec.ch

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0019_000.js
5c2ca88b76e1c9e7fe1b6c19ea3669ed62b95ec5bd22d6d753f4dc07a6158e2d
pdf-javascript-stream PDF /JS object 19 at offset 0x2DE 8256 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 10 long base64-like blob(s).
icc_00_off000029d9.icc
653b586c4707574ffcd648ba35494daed2c76ceafcf4c07d315ed961b1dc347f
pdf-icc-profile PDF ICC profile at offset 0x29D9 408 bytes
icc_01_off00002c74.icc
2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
pdf-icc-profile PDF ICC profile at offset 0x2C74 3144 bytes