Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3791cca40560c0d…

MALICIOUS

PDF

75.2 KB Created: 2021-06-11 15:05:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: f9cc5e3f6fb556775a6bed8fb8d2e990 SHA-1: f1406340887955f99bf29bd231a38b91da4e5193 SHA-256: b3791cca40560c0d6ad8f689c4e20b57b0c624f7fa93c8e77c20d25b2e8ef1c5
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for distributing malware or conducting phishing attacks. The document body, though heavily obfuscated, contains metadata related to 'wkhtmltopdf' and a search query, reinforcing the idea of a deceptive lure.

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://drafthe.ru/uplcv?utm_term=griffiths+electrodynamics+book+pdf PDF link annotation
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/p3eun78ghqir8i8c7tu5r55td5/19414889265.pdfIn PDF document text
    • http://webinside.pl/userfiles/file/varigelozalumifigufamer.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/21960648503.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/8469e3ebc2d918e7662eb4e36aeaa7c0/91892023916.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb506ac9ca6---tazis.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/9adec6588ba1f05dafa38981fe0e1185/97324185160.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/7dfb77d69d9755c9a67ae0dcb7dbe14d/gezejanepudob.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/dbf0b8841522887101f676adb4a62667/laxodorujuror.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/fc3cbab6fca714ebd96b1ad75ed1dc1e/vorokefasunetexorasupilo.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e4d517aa3---98462577406.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160766a4ce3266---fataw.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/30670090120.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/8brkhg0e764i4oero4vu8fam0g/91930704284.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/80e7e61e68edf5711289d3ec665b92e3/19654932236.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0c7d96065---47282944067.pdfIn PDF document text
    • https://allianztc.ro/files/file/sazonifofomusatenurow.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_off0000e782.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE782 5732 bytes
SHA-256: eec24a78f746fff6c0f6092b8e18be33eddbe9fa42c4087fe42388e3d47bbb4e
font_01_sfnt_off0000fadd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFADD 11196 bytes
SHA-256: d889bf7a49099676535df6d39cef5543336fc780df777fa8a372b32219657dd0