Malicious PDF — malware analysis report

Static analysis result for SHA-256 861892aebe97d031…

MALICIOUS

PDF

90.1 KB Created: 2021-07-07 01:37:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: a7f6081546d3f9bbdb3c3a557b262caf SHA-1: c99fc865d64674cff51d783490008764bffd9228 SHA-256: 861892aebe97d031a6cdc6c8a8f3aab622c29a1af291b47fa0fe26ec8366f689
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF document that utilizes a link farm hosted on compromised websites to distribute malicious files. Heuristics indicate the presence of a download button lure and multiple links pointing to PDF files on various domains, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. 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
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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.
  • 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 https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db83fdc578b---90999200533.pdf In PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/2d35ce336d635a724a4c8a5dd7c80474/13846189803.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/ea65c426b31322d42198d3e9955b02ae/40200747682.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/m7inl4n0rj3t6ud9akeu23ka6i/23590275190.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/11496608485.pdfIn PDF document text
    • https://restavracia02.com/userfiles/file/xakemojanumidopavis.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/638747bcede767895c2d256b13656cc0/76131308803.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/44978803894.pdfIn PDF document text
    • http://fultonhighschoolclassof1977.com/clients/a/ad/adf64365ba34d951c098eb677b062caf/File/sutulixugudat.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/c29c479a54a36fa9c5b456ed90e0309a/1045837337.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/60ce037c6acf47cdab1ac29727d2be5c/feberemi.pdfIn PDF document text
    • https://thietbidiensino.vn/media/ftp/file/mapolelebuzepawufevizosek.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/1519685198.pdfIn PDF document text
    • http://bakoca.hu/files/file/3686617856.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d8dcb7909dd---17947565809.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607585fb6be6a---vigedatipuwa.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/v7qp3hrqp5cqlogl96ccnuhua5/xerasumipisef.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a0368de92ad---6570049740.pdfIn PDF document text
    • http://indyztyle.com/ckfinder/userfiles/files/gekowomiwilabukamina.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/0af200fd817b9f7b04e7d63ce89fc287/jiwelamofoxemawageti.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/zotalamemaresakeviwisu.pdfIn PDF document text
    • https://presentkompaniet.com/img/content/file/gefuritufagus.pdfIn PDF document text
    • http://hbleg.com/admin/userfiles/files/fejuwufavavipas.pdfIn PDF document text
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/c33ff69447f198294761d026938de2a1/pavolipesokupubulo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=if+not+forever+by+durjoy+datta+pdf+downloadPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11000 10816 bytes
SHA-256: e202b0164bce84ecf19a23ccf362b61fc70ba16ee3886a4db2c051f6b9fbaa6f
font_02_sfnt_off000128ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128EA 18376 bytes
SHA-256: 6481c0ffe748962ffaab41bdc2b3f0511f258a46b6d77486aa3ec234fa3c6add