Malicious PDF — malware analysis report

Static analysis result for SHA-256 d762dc37c2c9968d…

MALICIOUS

PDF

75.3 KB Created: 2021-09-01 16:31:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8d16fdcc5329240d1ea642f59b854c3d SHA-1: c4cb34da68d05316a00cd29d1b1c03c0b9a64163 SHA-256: d762dc37c2c9968d2278a1989439fdde9a5879546f5410a22245a5d60e25aaec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites that host further PDF files. This behavior is indicative of a link farm designed to distribute malicious content, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly support its malicious nature.

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 http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d888024a65---5175089259.pdf In PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16070ccca282e5---70568665575.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/xaxekowosuloxutovi.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/vubedepoxaka.pdfIn PDF document text
    • http://asirakademi.com/resimler/files/vonufu.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1d0062288---22432216251.pdfIn PDF document text
    • http://taniaandjohn.com/clients/874109/File/navipubikov.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/30fe0fbc289c6f623845fb3cd14234b7/88087759995.pdfIn PDF document text
    • http://bhttourist.com/upload/fckimagesfile/sidunijevad.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/00896599f241e629e415227c64170ae6/divetepuvalotewixedamaru.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/jlr1ds6fegvqvu2s95lnt4obsr/56611818597.pdfIn PDF document text
    • http://www.greenfield-sustainability.com/images/files/wugowajelamolidiviku.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160835cf58e90c---26646889300.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607be06d1aa03---88583864625.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c2aa276357b---keregeravexovagap.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/jedifimema.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff0064ab7f0---51923726274.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1626647454.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=6th+science+textbookPDF 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_off0000bf56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF56 10424 bytes
SHA-256: 2a41beea0d87b659ae643440f128d3a9ff64111970d996147bc52dc7a83b1908
font_01_sfnt_off0000d6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F6 18952 bytes
SHA-256: 4a4a6fb760ac52aa24bcefa89b091c8315f14f341d409b00053773910a6beff0
font_02_sfnt_off000107e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1