Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bc4420d24c36085…

MALICIOUS

PDF

52.0 KB Created: 2018-06-11 09:56:09 -04:00 Authoring application: wkhtmltopdf 0.12.4 (via Qt 4.8.7) First seen: 2020-09-07
MD5: b29754ad17b6689ff2bf68fbc73eb9ce SHA-1: decbd74d6caba99834d00c7e143fe02e4512ec0b SHA-256: 3bc4420d24c360859ec92c77d878cbdf21a2037816ecf0243d81f72b8bcba73d
130 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell

The PDF file contains multiple embedded URLs that mimic educational content, specifically test answers. The ML classifier flagged this PDF as malicious with a high probability. The presence of a 'download button' heuristic further supports the lure. The primary attack pattern involves directing the user to download a malicious PDF disguised as educational material.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7480

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=solutions-intermediate-test-answers-unit-6.pdf In PDF document text
    • http://uncpbisdegree.com/download4.php?q=solutions-intermediate-test-answers-unit-6.pdfIn PDF document text
    • http://pkdrei.de/answer/solution/answer_solution_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://elpida.de/solutions/intermediate/solutions_intermediate_test_answers_unit_6.pdfIn PDF document text
    • http://annaca.de/answer/solutions/answer_solutions_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://ceolta.de/answer/solution/answer_solution_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://asian.cx/answer/solutions/answer_solutions_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://grappi.de/answer/solution/answer_solution_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://kiproe.de/unit/9/unit_9_test_answers_solutions_intermediate.pdfIn PDF document text
    • http://quicktradeimpex.com/reads-online/solutions-intermediate-test-answers-unit-6.pdfIn PDF document text
    • http://kannon.de/solution/intermediate/solution_intermediate_test_answers_unit_6.pdfIn PDF document text
    • http://kukla.lv/skola/Anglu_Val_TestuATB.pdfIn PDF document text
    • http://ryfles.de/answer/solutions/answer_solutions_pre_intermediate_test_unit_6.pdfIn PDF document text
    • http://uncpbisdegree.com/1/sony-kv-32xbr70-tvs-owners-manual.pdfIn PDF document text
    • http://uncpbisdegree.com/1/statephysical-science-2018-paper1-november-grade11.pdfIn PDF document text
    • http://uncpbisdegree.com/1/selected-works-of-rd-laing-knots-vol-7.pdfIn PDF document text
    • http://riverside-resort.net/1/well-done-teens-3-coursebook.pdfIn PDF document text
    • http://riverside-resort.net/1/unto-the-sons-gay-talese.pdfIn PDF document text
    • http://riverside-resort.net/1/why-can-earthquakes-signal-possible-volcanic-eruptions.pdfIn PDF document text
    • http://uncpbisdegree.com/1/the-best-of-dick-dale-15-classics-from-the-king-of-the-surf-guitar-guitar-recorded-version.pdfIn PDF document text
    • http://uncpbisdegree.com/1/the-eagles-prophecy-eagle-6-simon-scarrow.pdfIn PDF document text
    • http://uncpbisdegree.com/1/service-tv-user-manuals.pdfIn PDF document text
    • http://riverside-resort.net/1/uni-of-melbourne-acceptance-rate.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://www.scribd.com/document/176581910/Units-2-3-Test-Solutions-IntermediateIn PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=617350In 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://www.scribd.com/.../Units-2-3-Test-Solutions-IntermediateIn 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_off00007e1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7E1E 14128 bytes
SHA-256: a521f209489497607bab32f93d84dceaa2a802315d50f2fc98f75f9063181f84
font_01_sfnt_off0000a920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA920 9076 bytes
SHA-256: e69e84dceb50283d233d7edc9590975e68da5fca0f313535989e5371be7a807d