Malicious PDF — malware analysis report

Static analysis result for SHA-256 88703012fc880738…

MALICIOUS

PDF

104.5 KB Created: 2021-06-17 07:59:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: b8d2cf39bef8d68da70c6c7053c09c53 SHA-1: 4e1c860de65c30bb760162a9f0d4de20a4f77e10 SHA-256: 88703012fc880738ff1420616fa2f3230804437fe78edab2337f8cc735043d15
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://cructi.ru/uplcv?utm_term=science+olympiad+water+quality+cheat+sheet PDF link annotation
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/4b8c66516c8729c9ff69908a9452ab54/88525812212.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/alfo13as29hqff5d5jb24k7ch6/17381865968.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/88451675839.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/f27fc61a4985e82128a58c4814d09217/38605290228.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080407b6f240---zinupirofuboxusibi.pdfIn PDF document text
    • http://adveotec.com/img/file/pimeviwewad.pdfIn PDF document text
    • http://teplospectr.ru/images/files/xugajetu.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/rdco1ah5qbdk9ga5ta4dkhdhfu/59961305941.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b131fa6ee84---67499526664.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160af5400ea3e7---67726724623.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607331c9b74e5---16041007320.pdfIn PDF document text
    • https://afayl.com/userfiles/file/66366531083.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021051707551875.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab69255d757---81808011414.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/d0fa80ade79af835c58749565b48e06d/puragewopabuv.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160abb03ccab87---kivonetofimokax.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/ditibadufaraxulogugagav.pdfIn PDF document text
    • http://axwelindia.com/uploads/kipib.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000158f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158F3 5736 bytes
SHA-256: 9c85fb57ddd71bdf683eeaab743a3cf122ac28ae77bfb3919d909a95a983a689
font_01_sfnt_off00016c64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C64 11832 bytes
SHA-256: a6ab9a520ba9c742b5c3755a456001a8f58e2d1f868f11f08c4f1ec37540fe03