Malicious PDF — malware analysis report

Static analysis result for SHA-256 df43eca494acfdb6…

MALICIOUS

PDF

92.8 KB Created: 2021-07-07 19:13:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96e3efcd9941f0020211756b2f477101 SHA-1: cb0d4ea431495601dc8e2541d4544b6780621e05 SHA-256: df43eca494acfdb62cde3dfd22840f1b524535bab5d97d7f3791aaaea0a82525
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document that contains numerous links to external websites, many of which are hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics suggests the document is part of a link farm designed to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/1skbbhh4sqr85qmg6kdbpdnlfr/59968946800.pdf
    • http://marcobernini.it/userfiles/files/vaxav.pdf
    • http://cnex.cc/images/blog//file/budivotuxusolup.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d57d3a83fdd---bopiremeragifuvizo.pdf
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/lotixizoj.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bb429b31abd---67233759943.pdf
    • http://bet-balance.com/userfiles/file/lumodatakepadexu.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/5eb14bf046ead67891782e365db869eb/nifoboxu.pdf
    • http://bagiez.de/userfiles/file/47383384827.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a883659c02a---galagovajuwulosib.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606efed0d956d---maronavakeva.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/4f669cf9cc26dc769ae448ca9a39799c/ruxilutumonikawumon.pdf
    • http://restravel.ru/ckfinder/userfiles/files/vapepovesifim.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa5cc214e9---wipeveritapu.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b412270df69---fagowiliv.pdf
    • http://zhongguohuachun.com/d/files/94793940450.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160809aeed6b5c---lasufopev.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d910076a251---zigefo.pdf
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/1160d91fd0660dd44713378662cd126b/luxanowazapesusadidel.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/cdrjie37mnismsj0focn23l7be/31958233882.pdf
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090a34b86aeb---pidaduv.pdf
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16080a453e6217---26958148207.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=hdmi+specification+2.1+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000106f1.bin
638bcf7292146b7b0a4f25798705c8b20e2cad487c7620cc3ed2c3e1226fbd0d
pdf-font-stream PDF embedded font (sfnt) at offset 0x106F1 17528 bytes
font_01_sfnt_off00013509.bin
730cade7cc686e8f6ac344cad547468ba19de40786313eb6fa2a9200fc153fc5
pdf-font-stream PDF embedded font (sfnt) at offset 0x13509 10864 bytes
font_02_sfnt_off00014e30.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14E30 16792 bytes