Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd8bac53bc2a714b…

MALICIOUS

PDF

70.6 KB Created: 2021-05-07 06:54:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: f244207fe34c6b18d7c7db7fc7251aea SHA-1: 1605b423c2c57b971f5f92c70432dc7d7a3a4dc6 SHA-256: fd8bac53bc2a714bbaa862a37e5f42e2652014f88b214aaa9f30ecb6d0e8e987
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for distributing further malware or conducting phishing operations. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chcial.ru/uplcv?utm_term=fnma+guidelines+for+401k+loans PDF link annotation
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16086aafae9fc8---7749189502.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/1eb1a9d4c17a26acfd45feefda710146/99642520874.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/0ppfkjmhlr0e8i5lotk55jb339/dawefizox.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/8f2a265557f47ca6abc549e64c057c01/rafijatakapozowetomeraze.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/f80aa5ccc95cb31a3f1ac33465acc124/dinizonugugek.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/b28b08c1766af89c404c1e3c55171a8e/gakapalolesiki.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca1a11a15b---nedoviwutakorafaxanamosa.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/kloo77h3j55c76qfc9sfldtivf/latokemadapulipevo.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16084946baf7b8---82298171138.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/a4652ec4332d4a7fdf9f83e7ffe8b882/dajem.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/77ceivskv0v4recmc359gdq1ve/jubepajakafewikapa.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/ef098a336af79f3ae401ab2ad0d4a057/tojisuvoxeviwosom.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/durum.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/dbea6c84dbfafc4a2160f6e1e6d34c87/46734002244.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d9d526624---77595177415.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_off0000d91c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91C 5528 bytes
SHA-256: d36ec575d40c0bd92042b3454d10c911bc31631fd4805b4dd79f751bf214fa98
font_01_sfnt_off0000ebe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE0 9988 bytes
SHA-256: 1dd6b8208952befe0e7af24f2704ebf1675e0ea5834e92fa34e8e098ea28f0e2