Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd51d67669524feb…

MALICIOUS

PDF

6.8 KB
MD5: 198fecbf7bba08cfc45c8e19f3bfe171 SHA-1: 5b7c9d7afdd78fc28dc2a2cc0101f157def00567 SHA-256: bd51d67669524febc589740562e63fd5c843b6b260726ced3e56ca61678c2237
94 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that exploits CVE-2014-0496 using app.addToolButton/removeToolButton. The JavaScript is obfuscated and decodes a base-26 encoded string which is then evaluated. This stage is responsible for downloading and executing a second-stage payload. The presence of XFA forms and AcroForm buttons with actions further indicates a malicious intent to leverage PDF features for exploitation.

Heuristics 7

  • app.addToolButton/removeToolButton — CVE-2014-0496 critical CVE exact CVE_2014_0496
    PDF JavaScript combines app.addToolButton() and app.removeToolButton() with heap-spray shellcode markers — the public Adobe Reader/Acrobat ToolButton use-after-free exploit shape for CVE-2014-0496. (identified after JavaScript deobfuscation)
  • 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.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • 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/2.8/
    • http://www.xfa.org/schema/xfa-template/2.5/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0003_000.js
d4f8b60a1155a97254246b33109668f2f9d6cb0f29b285729cafc353fb6eedd7
pdf-javascript-stream PDF /JS object 3 at offset 0x409 15530 bytes
base26_stage_000.js
9349b6ff3cdddf2cf7cdb663f6e012a8a722de9b342ffd364d0d98f78ee6cd94
deobfuscated-js base26-decoded JavaScript (decompressed) at offset 0x60D 5913 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 44 eval/decoder/string-building token(s).