Malicious PDF — malware analysis report

Static analysis result for SHA-256 056c1ac0e892b506…

MALICIOUS

PDF

8.3 KB
MD5: 1f3945c0b47c7338ef71c0081f28505a SHA-1: 21f7dad106cc607101d3274ab32f3e1ee6b53fbc SHA-256: 056c1ac0e892b506afd579df8031a3c4608083272d5bd3419aec5d459901faf9
158 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains obfuscated JavaScript that utilizes eval() and String.fromCharCode() functions, indicating an attempt to execute arbitrary code. This JavaScript exploit cluster is a strong indicator of malicious intent, likely to download and execute a second-stage payload. The ML classifier also flagged this PDF as malicious with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8836

Heuristics 7

  • 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)
  • 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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000032b.bin
8761d1709b96a35cf89f25dd2e3fff5a92bbcf6e547e65954156c175a15638e0
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x32B 3250 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
stream_003_off00000b85.js
2d0e1efdfa6110385aac29417e1a9d65e8e7ccab9271cd5a5863752fe736691a
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xB85 372 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
objstm_0025_00.bin
3f04dc237a398112c8aa903c433f4a3af5cbca88f59d3db86700bf8b0de756ad
pdf-objstm-decoded PDF /ObjStm 25 0 obj (inflated) 432 bytes