Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b3f93beff83c6c8…

MALICIOUS

PDF

83.6 KB Created: 2021-09-07 03:57:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e63bb5df085d07367aec8eb52e81ffde SHA-1: a370d476a4cf850e7eb9ab81c7d3b4944dd3df84 SHA-256: 6b3f93beff83c6c82c68639e2e43999bdf9cc2da0613ef5b291d2e680a041a2e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/1cedb9d449b5ba261f98913871103720/rijuvaxakikaranumile.pdf In PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160799cdf0d689---sujanuporuwix.pdfIn PDF document text
    • https://zabulgaria.org/userfiles/file/kowavozedokisiwopiwegav.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/q8grn7pgr3lccamsui7updml21/petiki.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160a37379b4bc2---41966363666.pdfIn PDF document text
    • https://aedwea.com/upload/foto/sijogozax.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/72935245814.pdfIn PDF document text
    • https://rkdestate.com/userfiles/file/66210256384.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/fovemofovikori.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/masiputusowosakoranofi.pdfIn PDF document text
    • http://rwdwebwebdesign.com/img-aim/files/nuxat.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/34237434091.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070738286920---lavorewop.pdfIn PDF document text
    • https://huanghecables.com/d/files/44594840928.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/39f8r4v4vf9hfqae25l3qij6nj/masidosisesenum.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/sujorekesafinaxogowajezi.pdfIn PDF document text
    • http://washburnhs64.com/clients/f/f7/f75dc469904bb25755ea64d7551c4a95/File/93873347714.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071942dc643b---fexideluw.pdfIn PDF document text
    • http://partner-support.net/user_data/userfiles/files/nilopirel.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/49113596028.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/95384145737.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/gonhup5hm8ll572gcu5u1iqpt2/84654557011.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/99920565333.pdfIn PDF document text
    • https://amursvoidom.ru/media/files/43066791603.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=constructivismo+arte+pdfPDF 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_off0000dff6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF6 18608 bytes
SHA-256: c8ed087bfaf19f4af87949a0db38e1e8ed3565375ee61593d30d6c93d53fedf3
font_01_sfnt_off00010f46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F46 10932 bytes
SHA-256: f2562ac61fb48cff07e6b2b51ac098467d0ab8fe97569b337672a5ff1b3bfeac
font_02_sfnt_off000128ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1