Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b1d6b12ff9a356…

MALICIOUS

PDF

87.1 KB Created: 2021-09-17 18:15:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5eaf9d1abbf4b8d0c44c9b7ef72c2246 SHA-1: 9c4a1974ebcda312d039ad2328f7197578796d14 SHA-256: a8b1d6b12ff9a356847b6f3ba516a68695c01925538ef5f0fa3420784e2c6f01
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm on disposable hosting, indicating a phishing or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The primary attack vector appears to be luring the user to external sites via embedded links, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crysiq.ru/uplcv?utm_term=invention+and+inventor+pdf PDF link annotation
    • http://www.dilipprabhavalkar.com/images/file/44263375041.pdfIn PDF document text
    • http://seychelles-resort.com/images/blog/file/widevinutober.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/witebaxikawatalarepek.pdfIn PDF document text
    • http://vssteel1999.com/ckeditor/userfiles/files/1973510572.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/31084078411.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/12576913919.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ganotoxekosodisomati.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/99754482345.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/tebebiwupazade.pdfIn PDF document text
    • http://rancholasmonturaspremios.com/campannas/file/28936134458.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/wemolevudobubavoluxuze.pdfIn PDF document text
    • http://shopphutungmayphat.com/upload/img/files/80588489108.pdfIn PDF document text
    • http://pincesorvarshop.hu/editor_up/fabidikatorimafexukovaz.pdfIn PDF document text
    • https://digicpictures.com/downloads/sagijanunixukuvido.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/25042841505.pdfIn PDF document text
    • http://gucaoyun.com/uploads/file/030953337569.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/5461101387.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210901211640468.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/1700601492.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/dekufuxiwiw.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/pasetonejudexuzebemixufa.pdfIn PDF document text
    • http://www.tm-africa.com/beta/public/uploads/cms_filescms_files/boxamuza.pdfIn PDF document text
    • http://pressvaluation.net/FCKeditor/editor/filemanager/connectors/userfiles/file/96172607154.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/84995261961.pdfIn PDF document text
    • http://orvositudasbazis.eu/images/upload/file/88264228334.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16138b7cf57edb---nitiw.pdfIn 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://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_off0000eef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF6 18204 bytes
SHA-256: 19c5c8f1feba76051c72142185dbfb13e3269baa1c198a37246fd7f0d4f7307d
font_01_sfnt_off00011f09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F09 10296 bytes
SHA-256: ad961e04bec23e8a5649c3baa61e5611a34429f4d853b70ebfc953350324dddd
font_02_sfnt_off00013658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13658 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1