Malicious PDF — malware analysis report

Static analysis result for SHA-256 25f9bc5c68cd777a…

MALICIOUS

PDF

35.2 KB
MD5: e8ca8d40d091b5557cf39b2b0e1567e2 SHA-1: 1a234cc407a09251af237cda411c80655d6a48a4 SHA-256: 25f9bc5c68cd777a720ce4b58e4f52e427d77691c18c200ec86190af348b6dab
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript T1559.002 Component Object Model

The PDF contains embedded JavaScript and a Flash object (Adobe.swf), both of which are commonly used to exploit vulnerabilities or deliver secondary payloads. The ML classifier strongly indicates maliciousness. The embedded JavaScript stream, decoded using String.fromCharCode and ASCIIHexDecode, likely facilitates the execution of the embedded Flash content, which in turn is expected to download and execute a further stage.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 9

  • RichMedia (Flash) high PDF_RICHMEDIA
    PDF contains /RichMedia (Adobe Flash) which is a historic exploit vector
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/2.6/
    • http://www.xfa.org/schema/xfa-template/2.6/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
Adobe.swf
8f9c84c8c00bc62ae296a81fac6640aa852ea67548abc1bd639aa0da1a1696c4
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0xE33 27347 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact entropy is 7.99, consistent with packed or encrypted content.
javascript_obj0006_000.js
ec08c806faf6c67003ff58123200fce4c91e4191349ba65295aa8ac7dce3b375
pdf-javascript-stream PDF /JS object 6 at offset 0x105 10470 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).