Malicious PDF — malware analysis report

Static analysis result for SHA-256 398a102838da1886…

MALICIOUS

PDF

76.6 KB Created: 2021-09-03 03:04:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 622286cb179205c39b568157280b3838 SHA-1: f4956364a70e9a7dcb16284dfbbd185a44ace780 SHA-256: 398a102838da188665fc271b57ee7afe513643b0e7c4c34b903e8bee00c9082c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by a ClamAV detection and an ML classifier, indicating it likely contains malicious content. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress uploads and disposable hosting sites. These links are likely intended to lure users to phishing or malware distribution sites, aligning with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cba36099a5c---21631473190.pdf In PDF document text
    • http://bbfederico2.net/userfiles/file/xogilivilexot.pdfIn PDF document text
    • http://videlec.be/ressource/file/13971641360.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/sufavisuret.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161094aa665713---50692765300.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/zovixedesagelopofulatokof.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/zudifa.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/63757966312.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160c23dea2f5bf---zemoro.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/kepifita.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/bafibizefozozuk.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/pibetegerebubofamatofu.pdfIn PDF document text
    • http://turinhotelcompany.com/userfiles/files/titosesifanafabuzo.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/7878ea28c98083e4877c1e29842d62a0/18481129091.pdfIn PDF document text
    • http://myredm.ru/uploads/file/movujenunuruwowobenamafe.pdfIn PDF document text
    • http://hamyarsanatco.com/ckfinder/userfiles/files/83936658428.pdfIn PDF document text
    • https://brakos.it/file/93197983232.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/nupapogojatadozebag.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f96efabde0f---mexodumetufawufuleneb.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf75148312---mimuvi.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-8-7/20210807104453492631.pdfIn PDF document text
    • http://roocenter.ru/upload/file/duvopaxuzazeseji.pdfIn PDF document text
    • http://maduraigarlandshop.com/userfiles/file/61861154289.pdfIn PDF document text
    • http://xenangheli.vn/public/files/pewemodujirogisejiz.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/dakekijoxopufovaxulekoli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=nelson+textbook+of+pediatrics+21st+edition+pdf+amazonPDF 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_off0000c3fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FC 11324 bytes
SHA-256: 44467d0c00b438b2aa3cf5d9d84e5432fb858be8aca2ccf2899d1fb545984512
font_01_sfnt_off0000de93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A5 17468 bytes
SHA-256: 2255347c8bff0dc55296370e816451ae53c86bdb1d095e49707fd30bc1a79930