Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed4c8a7257edd0ab…

MALICIOUS

PDF

88.3 KB Created: 2021-08-15 06:14:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1dca71a82abd6193c58a324a202fbc80 SHA-1: 8898acfc8ddc592c42513ae77200e5a5207932a1 SHA-256: ed4c8a7257edd0abf8f384e93b4f8e83c8714a595cd0f9b5d87f3b1137062783
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm or phishing lure. The PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://yeosingol.com/FileData/ckfinder/files/20210628_5F44D91D648242E0.pdf In PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b472d5be3c9---76884604789.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/62195074965.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/mamunoweborakeraf.pdfIn PDF document text
    • http://mq-water.net/upload/6166469507.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cb993c6b896---41403737842.pdfIn PDF document text
    • https://kaktutzhit.by/uploads/files/38508030118.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5830bb2e67---4749440916.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/ligemaguju.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/zitagis.pdfIn PDF document text
    • http://stl-hk.net/userfiles/vofodotaxodasemila.pdfIn PDF document text
    • https://oriental-kitchens.com/userfiles/files/kuluwizewivijisawiwof.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/gafivojexulejalilurabozuv.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/18ssmld2549e4649bvos50mcu5/vepesupafidonipifeg.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f90c37ccd2e---funed.pdfIn PDF document text
    • http://ozdesignhouse.com/app/webroot/uploads/files/17610760178.pdfIn PDF document text
    • https://brtim.com/uploads/wysiwyg/files/48061282857.pdfIn PDF document text
    • https://33mobility.net/uploads/files/41931938165.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210713141341.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/kofekijutisefuxunoresuluk.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa5d1d2b3e---4134299440.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a9919ea1c2---birubabovel.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c18a65eb3---wumojijatalilapabefexu.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb80714e241---47432548285.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/52db717de78cd277b0ab2704f71d122c/36439931888.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=angle+iron+dimensions+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_off0000f7ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EF 16872 bytes
SHA-256: 5ed553f70465c7540e9afc3971479aecfb1f31555d9d3e84278b7571660fd926
font_01_sfnt_off00012410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12410 10560 bytes
SHA-256: 736ec5aa7a679f321ccd1f87d0ec54a01abc807cc518c8e842c81a745b01fa0c
font_02_sfnt_off00013bdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1