Malicious PDF — malware analysis report

Static analysis result for SHA-256 52d4cc188396d8f1…

MALICIOUS

PDF

32.4 KB Created: 2018-06-11 08:16:14 -04:00 Authoring application: wkhtmltopdf 0.12.4 (via Qt 4.8.7) First seen: 2020-08-10
MD5: d9851e875042246908f49d53ea79232d SHA-1: 7a819d1488b6fe8d8e3c0f42671a4b70ebe4d54f SHA-256: 52d4cc188396d8f162251c7967c3d3bb321163a29543314da76a046fe3bdfa61
130 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF contains embedded URLs that point to a domain associated with malicious downloads. The ML classifier strongly flagged this PDF as malicious. The document body, though partially corrupted, includes references to download links, reinforcing the lure. The presence of these elements suggests the document is designed to trick users into downloading a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9340

Heuristics 4

  • Fake 'free download' SEO-poisoning PDF critical PDF_SEO_FAKE_DOWNLOAD
    The ML classifier flagged this PDF AND it carries a visual download/call-to-action lure AND an off-domain server-side download-gateway link whose query string names a document payload. This three-signal conjunction is the fake-document / 'free PDF download' SEO-poisoning delivery pattern: the page is padded with benign decoy links to dilute classifier scores while funnelling the victim through the gateway to malware/scareware. Acting only on the conjunction keeps benign download-bearing PDFs from being misflagged.
  • PDF carries a PHP-gateway SEO-spam PDF link farm medium PDF_SEO_PHP_GATEWAY_LINK_FARM
    PDF contains four or more clickable links whose target is a `.php` gateway with a multi-word search-PHRASE document slug embedded after it (e.g. 'index.php?.../binary+options+trading+nz.pdf' or 'pdf.php/cialis-dosage-side-effects.pdf'). Legitimate PHP-served documents use a filename or numeric id, not a search-query phrase, so this is the generated SEO link-farm shape — pharma / binary-options / 'free download' spam that ranks for queries and routes users into payload/redirect chains. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://uncpbisdegree.com/download3.php?q=the-nature-of-gods-marcus-tullius-cicero.pdf In PDF document text
    • http://uncpbisdegree.com/download4.php?q=the-nature-of-gods-marcus-tullius-cicero.pdfIn PDF document text
    • http://www.stoics.com/cicero_book.htmlIn PDF document text
    • http://www.mmdtkw.org/VCicero.htmlIn PDF document text
    • http://latin.topword.net/?CiceroIn PDF document text
    • http://www.freedomformula.us/articles/gods-law-the-foundation-of-free-government/In PDF document text
    • http://www.tertullian.org/fathers/nepos.htmIn PDF document text
    • http://riverside-resort.net/1/the-centennial-history-of-illinois-vol-2-the-frontier-state-1818-1848.pdfIn PDF document text
    • http://riverside-resort.net/1/syd-field-screenwriters-workbook.pdfIn PDF document text
    • http://riverside-resort.net/1/service-manual-renault-modus.pdfIn PDF document text
    • http://riverside-resort.net/1/siege-and-its-ancient-near-eastern-manifestations.pdfIn PDF document text
    • http://riverside-resort.net/1/the-practice-of-spiritual-direction.pdfIn PDF document text
    • http://riverside-resort.net/1/snowplow-polka.pdfIn PDF document text
    • http://riverside-resort.net/1/sketchup-pro-7-electrical-drawing.pdfIn PDF document text
    • http://riverside-resort.net/1/the-outsiders-se-hinton.pdfIn PDF document text
    • http://riverside-resort.net/1/transpersonal-research-methods-for-the-social-sciences-honoring-human-experience.pdfIn PDF document text
    • http://riverside-resort.net/1/thassos-map.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://www.britannica.com/biography/CiceroIn PDF document text
    • http://www.iep.utm.edu/cicero/In PDF document text
    • https://en.wikipedia.org/wiki/CiceroIn PDF document text
    • http://oll.libertyfund.org/titles/cicero-orations-vol-3In PDF document text
    • https://en.wikipedia.org/wiki/De_Natura_DeorumIn PDF document text
    • http://www.bartleby.com/12/8.htmlIn PDF document text
    • http://www.bartleby.com/people/Plutarch.htmlIn PDF document text
    • http://www.bartleby.com/12/In PDF document text
    • http://www.bartleby.com/268/2/11.htmlIn PDF document text
    • http://www.bartleby.com/nonfiction/In PDF document text
    • http://www.bartleby.com/people/Bryan-WiIn PDF document text
    • http://www.hup.harvard.edu/collection.php?cpk=1031In PDF document text
    • http://oll.libertyfund.org/titles/addison-cato-a-tragedy-and-selected-essaysIn PDF document text
    • http://go.microsoft.com/fwlink/?LinkId=521839&CLCID=0409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=246338&CLCID=0409In PDF document text
    • https://go.microsoft.com/fwlink/?linkid=868922In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=286759&CLCID=409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=617297In PDF document text
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000447d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x447D 9888 bytes
SHA-256: e53c8e7e1daafcc61e1274ac881e547c75241688ec57a9418f25095b6fd9a09d
font_01_sfnt_off00006426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6426 7080 bytes
SHA-256: b91bda582e7c2ca40a42aca514bfe0f4704ed0b98ce69a5152127dc1b75c12c0