Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b086b36f51493f8…

MALICIOUS

PDF

76.3 KB Created: 2021-09-06 19:33:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6e966819183499715463422bd8a24e85 SHA-1: 7bd75461ae1f2cc9212cecb9fe9da12d5cf2dcc2 SHA-256: 5b086b36f51493f852a47a4525a5983a4783864f12ff488ddc7fd20d9421e1c9
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many URLs pointing to compromised WordPress sites. This suggests the PDF is designed to redirect users to potentially malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/fc6f5529e12b94290c4f09924ac5e731/11062594893.pdf In PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/iv7fu2igm7nl26idt7pgibpac4/nunesezoduvabolobe.pdfIn PDF document text
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a04a7a8d9a2---12159431172.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/gudiwanekil.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1607f65af18ee7---21809206729.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160747e8b90009---77736690644.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/770e9003a9b4090066280ad2fa59682e/57861289291.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/62138774971.pdfIn PDF document text
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/98182fc328fc30683d1b4d07cf0c7b93/musoni.pdfIn PDF document text
    • http://barcabianca.eu/upload/file/45109535405.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/80113a1755c05589ae4d52d24e43ea47/61690758162.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160781b8f98445---80112704709.pdfIn PDF document text
    • http://droneducational.com/admin/userfiles/file/wujalojoginina.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/3a94f9a999f69efcffbb76fadac847c9/65525117715.pdfIn PDF document text
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611463e66ec75---zenulefadek.pdfIn PDF document text
    • http://farmina.ru/uploads/files/36714037025.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/fnhrocma7eec70vma9p2k0fnsf/jorora.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c38994383---figolivakukabaza.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/74260872161.pdfIn PDF document text
    • http://luingpyrex.cz/foto/Image/file/kebejuxuvavoworokaxomomi.pdfIn PDF document text
    • http://verduciautodemolizioni.it/userfiles/file/vegiwugene.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f2c9db7354e---limaturalulugomojekuje.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608fcd015f71d---kokumurifevojonozuriz.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/6ed2bfc0bf0ee8fad5d0c751e1171ed2/49267484593.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608c36fab8a6d---61668425616.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=vocabulary+worksheets+5th+gradePDF 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_off0000c6dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000def3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF3 11088 bytes
SHA-256: 3bb00709af396271afcbdbb7bcefe98dca127f6c226700343a06ede55377a37a
font_02_sfnt_off0000f8f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F1 16240 bytes
SHA-256: 92ea2fba5898bd0ecd6e4cf3845b765b4078b548b4b53a1634f56ef7df99dcdf