Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d55527d898d2277…

MALICIOUS

PDF

87.0 KB Created: 2021-08-12 14:43:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bd36a82ae281ca1ef3f9286d7512a352 SHA-1: e5a6112584d638c2f271bce7566c9fe768750ff8 SHA-256: 0d55527d898d227718a08f8be8d49656e5a668a67ec7b611479e56b930c5ab38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics reveal it functions as a link farm, with multiple URLs pointing to compromised WordPress sites and disposable hosting, likely to obscure the final destination. The embedded URLs and the nature of the link farm suggest a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609044f792f68---valobonuzifa.pdf In PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/5smpgv92c1jks8ohviqhn0c43v/77764880800.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/e9ekggujrdav09nb4jmfi2jkln/13866363426.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f819545acf---4616757227.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/menide.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f329b142cd---37176927374.pdfIn PDF document text
    • https://www.herewardcarpets.co.uk/wp-content/plugins/super-forms/uploads/php/files/onbq947rbiv7hctrgo288rd9jn/davupu.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861be89edc1---natuvav.pdfIn PDF document text
    • https://seitonsolutions.com/ci/files/50946040540.pdfIn PDF document text
    • https://eseninternational.com/uploads/files/8887746702.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/tuwibajogomalinisagi.pdfIn PDF document text
    • http://hungbuloon.com/media/ftp/file/20826134698.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/gps35p70or81p8aelhfn347ac1/1167220805.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/96211605868.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/febamepitodutipotaxuna.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/230115466.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a27035adddf---71663027083.pdfIn PDF document text
    • https://liftsystems.ro/LiftFiles/file/6385581264.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/woforikovadidozegevibonek.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/77469365021.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/rudiremor.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/2eb490a771460a3b36966d3c696c3f17/61228421487.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608321778ba4f---sodomavoduwaxilolizimuv.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ee609facb---77595918632.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b5638807fb9---zamupove.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/zabeligimopuwukomoxar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=elementos+de+m%C3%A1quinas+niemann+pdf+em+portugu%C3%AAsPDF 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_off0000e8db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100ED 19688 bytes
SHA-256: d85a11695540b798703674146da92ae150254453826070a2ab9caff8331e1eb7
font_02_sfnt_off00013192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13192 11408 bytes
SHA-256: fafbcb25272ae0ae327b5ebca88c6db14ac9e00dba5988600f12af03e799cfdd