Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6e761fdcde0bcd8…

MALICIOUS

PDF

6.8 KB
MD5: f5279093ec1cbc14ade011e63906f4ec SHA-1: df8f515545b6655fbabf053ed95f7bcf43c7580f SHA-256: a6e761fdcde0bcd8c609d3ac03a81569949196cd6fb8a64ef6ce69beabbf65d5
94 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the CVE-2014-0496 vulnerability by using app.addToolButton/removeToolButton. This JavaScript is further obfuscated and decodes a base26-encoded stage, identified as 'base26_stage_000.js'. This stage is responsible for downloading and executing a subsequent payload, indicating a downloader or dropper functionality. The specific family could not be determined due to the obfuscation and lack of further indicators.

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
458a9b220477b399c11991d9ad9f8cb4f6d45a9c7268c3f876402994d691a1c1
pdf-javascript-stream PDF /JS object 3 at offset 0x409 15604 bytes
base26_stage_000.js
8c69f550d6ff0d52bcbde1d8f0dc48acb8b5c2669959ee80624c440d6fafad2b
deobfuscated-js base26-decoded JavaScript (decompressed) at offset 0x60D 5943 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 44 eval/decoder/string-building token(s).