Malicious PDF — malware analysis report

Static analysis result for SHA-256 b240827f1fd5af21…

MALICIOUS

PDF

48.9 KB Created: 2012-11-13 13:28:58 +03:00 Authoring application: Adobe Designer 7.0
MD5: 0a40e90a3f376f96b00b6be18bb672f3 SHA-1: 684ab6ca1322edf709362b6465267bd20f6db135 SHA-256: b240827f1fd5af21c4e1063fbd2f195a57dc8fc0af2170fbef88ed581611ff75
158 Risk Score

Malware Insights

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

The PDF file contains multiple high-severity heuristic firings, including PDF_EVAL and PDF_XFA_SCRIPT, indicating the presence of risky executable scripts within an XFA form. The ML classifier also flagged this PDF as malicious with a high score. An embedded file, 'embedded_file_obj0048.bin', was identified as a suspicious artifact, likely containing the second-stage payload. The presence of these elements strongly suggests an exploit attempt designed to download and execute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 9

  • XFA form contains risky executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose script block contains exploit, submission/launch, or shell-execution primitives. Ordinary LiveCycle print/update scripts are left as generic XFA/JS signals unless stronger behavior is present.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • 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.
  • 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
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/

Extracted artifacts 8

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0046.bin
c06dcd026a7ea0536b63e07ce688691b585339a3ab7ff59065e546b56308c7bb
pdf-embedded-file PDF EmbeddedFile object 46 at offset 0x7524 85 bytes
embedded_file_obj0047.bin
f20aceb8dbc16d07642c756ca1ccc141a87f1f44f1a99949a4c6a6a8678b4c98
pdf-embedded-file PDF EmbeddedFile object 47 at offset 0x75D6 1526 bytes
embedded_file_obj0048.bin
6223c0d07823207c76b1076b542c91ef5eaaaab1988bdaaa757e9a230fdf0e5a
pdf-embedded-file PDF EmbeddedFile object 48 at offset 0x78A6 6101 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0049.bin
0b7fe2cbe79087012463f41fc1327af7a43b4981b1049b2448bcaa170e431454
pdf-embedded-file PDF EmbeddedFile object 49 at offset 0x8526 171 bytes
embedded_file_obj0050.bin
cb11c8f9d1f88e25fb66ce82b3736fe08cf8253503209e92cac18f94ff0cdb0d
pdf-embedded-file PDF EmbeddedFile object 50 at offset 0x85EF 6434 bytes
embedded_file_obj0051.bin
57045217c453d4674a08ad8778674bf199a7989a9505424a1815c016e6bb412f
pdf-embedded-file PDF EmbeddedFile object 51 at offset 0x8ACC 212 bytes
font_00_cff_off000012d0.bin
23831e143e2e1a484b95ee765b15d94562c951468b895c080e655667dc04ddf0
pdf-font-stream PDF embedded font (cff) at offset 0x12D0 31178 bytes
font_01_cff_off00008c31.bin
4fc69e9eb08c766ddd22ec85e8f9f840b25ab41e48750b42b8134fffaa9b56fb
pdf-font-stream PDF embedded font (cff) at offset 0x8C31 4074 bytes