Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3ff234d8402bdb4…

MALICIOUS

PDF

49.3 KB Created: 2010-02-23 12:29:53 -08:00 Authoring application: Adobe LiveCycle Designer ES 8.2
MD5: 050b0add9a8a1d18e6007018c6c3be34 SHA-1: 9651459e008f90d3e281960d1f8fe074200a37f1 SHA-256: a3ff234d8402bdb4139274e0f7889ce1336be1dedd2068b6cff8270d3e67a4f3
112 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript and an embedded file, indicated by multiple PDF_JAVASCRIPT and PDF_EMBEDDED heuristics. The ML classifier strongly flagged this PDF as malicious. The document body suggests a lure to open embedded attachments, and the presence of 'regedit.exe' among embedded files points towards potential system modification. The embedded JavaScript likely attempts to download and execute a second-stage payload or exploit a vulnerability, though the exact script content is truncated and obfuscated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 9

  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 2 image(s), only 2 text block(s), carries a click-outward action, and is only 49 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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
  • 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/1.0/
    • http://www.xfa.org/schema/xfa-template/2.4/
    • http://www.xfa.org/schema/xfa-data/1.0/
    • http://www.xfa.org/schema/xfa-locale-set/2.7/
    • http://www.xfa.org/schema/xfa-locale-set/2.1/
    • http://ns.adobe.com/xtd/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://www.xfa.org/schema/xfa-form/2.8/
    • http://purl.org/dc/elements/1.1/
    • http://cgi.adobe.com/special/acrobat/update
    • http://www.w3.org/1999/xhtml

Extracted artifacts 12

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0001.bin
c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
pdf-embedded-file PDF EmbeddedFile object 1 at offset 0x44 85 bytes
embedded_file_obj0002.bin
0cae1494b9c99505bf126e683a1a8be36bc8d5e793ab829e266d6e2fd62ccac3
pdf-embedded-file PDF EmbeddedFile object 2 at offset 0xE4 1466 bytes
embedded_file_obj0003.bin
1b57e7c1e4bc1f8daf7cdf9c6223b19580c93789063a99232ed1cb040470df13
pdf-embedded-file PDF EmbeddedFile object 3 at offset 0x6E9 9148 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 long base64-like blob(s).
embedded_file_obj0004.bin
f47c3dc8c4eeb64abc2cc332be719add15af6ce6dfdcdb477c08a1aefdbe7477
pdf-embedded-file PDF EmbeddedFile object 4 at offset 0x2AF1 11740 bytes
embedded_file_obj0005.bin
226eeacc5eecef2a05ca480f144ff6936594e20b5c7672e8f29f25c8bea65a56
pdf-embedded-file PDF EmbeddedFile object 5 at offset 0x5918 2928 bytes
embedded_file_obj0006.bin
4cb349134bdb5f1a1c03281df9b53128ebe947f235398a912a4f0a9f638b24d5
pdf-embedded-file PDF EmbeddedFile object 6 at offset 0x64D2 200 bytes
embedded_file_obj0007.bin
d51b9fc28b592405fb598e711d1495e1421571073bc2e8542d55389768716c06
pdf-embedded-file PDF EmbeddedFile object 7 at offset 0x65E4 835 bytes
embedded_file_obj0008.bin
e65f1e07bc965092b3153e64a1e8777a909cc47a98c0e2a10d38c47def2e6652
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0x6971 291 bytes
regedit.exe
855c3dab85b37ccdd90fc17c1cc4bcea8590d1c92da6ad10b8cfb35e601de314
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x6B38 154 bytes
javascript_obj0046_000.js
f574e4d51594d1a8fd22e125b109b827c437aa898edc78babb62dbb93f8744f8
pdf-javascript-stream PDF /JS object 46 at offset 0x8C81 1532 bytes
javascript_obj0047_001.js
4a1aca004cf20431c9a66dce85404a6411a54d881a6c257882260ffc972a13eb
pdf-javascript-stream PDF /JS object 47 at offset 0x92B5 870 bytes
javascript_obj0048_002.js
826c5622c798d67e5281cca7e05933dddc90ccdcb0a6177c9f7d06f11bef8f7f
pdf-javascript-stream PDF /JS object 48 at offset 0x9652 2795 bytes