Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fb8ad3818cdfa17…

MALICIOUS

PDF

35.2 KB
MD5: 09d5cfb28d078329ff81ba93f5b0b7b5 SHA-1: db0919534327f25fd7b50bb6299f6adc6f39b02a SHA-256: 8fb8ad3818cdfa17df035d7eb2fe4b85a9c5f225179bdaf786673cac1e493974
132 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF file contains embedded JavaScript and a Flash object (Adobe.swf), indicated by multiple heuristic firings including PDF_JAVASCRIPT, PDF_JS, and PDF_RICHMEDIA. The ML classifier strongly flags this PDF as malicious. The embedded JavaScript, although obfuscated, likely attempts to download and execute a second-stage payload. The presence of these embedded objects suggests an attempt to exploit vulnerabilities or trick the user into executing malicious code.

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 0xE2B 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
87d555c362e84113105707e59e3cd90ad875755f0e38df24b183d994a7ad7fe3
pdf-javascript-stream PDF /JS object 6 at offset 0x105 10464 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s).