Malicious PDF — malware analysis report

Static analysis result for SHA-256 b856cf2879241578…

MALICIOUS

PDF

78.3 KB Created: 2021-07-24 22:31:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 9f006651bc96dd927bf3bc052d3e77c9 SHA-1: 6b0fa84a56096d14c78a9c8789f7f6d7b13806f9 SHA-256: b856cf287924157805950faaa882c57e2a0d17eb3ce5fa1dcb21d1d8d708e80f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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 0.9953

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://campcolefamilyreunion.com/clients/82065/File/xivadimoxotopanoluxuze.pdf In PDF document text
    • http://autosoftware.company/autoresponders_images/files/newedelowexurezib.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/20023392022.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/sazubudimo.pdfIn PDF document text
    • http://atomicattack.com/atomic/fckimages/file/feretuguxatuwu.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8f147fd3b---beroso.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087812c08952---gubitamomo.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160740cff08969---nutevudunotapoz.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b90209b82d---43167643176.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a893f6a77f---raninenutedesafi.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d486882f6c8---26341796622.pdfIn PDF document text
    • https://mtmhomeschool.com/mycms/uploadedimages/editorUploadedImages/file/dolomefijakorifetasuneli.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/71405033648.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/zunowavopupimisozak.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7bf70d8dd---ponipodefizozepekupum.pdfIn PDF document text
    • http://cesishotel.com/res/wysiwyg/file/xivigisozupufarevo.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa43103dbe6---17368960931.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/9434f5b5cb639d1e27b2115559210cae/lubemipikerox.pdfIn PDF document text
    • https://kawanmto.net/contents//files/31898022557.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/37353786274.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/nonogemiribugero.pdfIn PDF document text
    • https://ctsgroups.asia/images/file/joxuv.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/14755764692.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/ziwukek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=company+seal+stamp+samplePDF 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_off0000cfb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB8 10364 bytes
SHA-256: a3c46fedce3113d2d78d115631be99dda97eea36f3f28bc6014d49982052d968
font_01_sfnt_off0000e734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE734 17084 bytes
SHA-256: 7ac84e6d87fa73accc9b354e095ec94425024c958dee4087c88e7c8d7feedb38
font_02_sfnt_off000113ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1