Malicious PDF — malware analysis report

Static analysis result for SHA-256 78f1f0351d1e6bcf…

MALICIOUS

PDF

89.4 KB Created: 2021-09-14 12:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 91a33883be4e3d04181a33faa894a0be SHA-1: e8b8d4bbe00d5b8290289eed0eb90c9dbc4b7add SHA-256: 78f1f0351d1e6bcf2f098175e8460eb835c6b3f8750f527495ceda47cbad0ed7
134 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 external URIs, including one pointing to 'smidgel.ru', suggesting it acts as a lure to external malicious sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the idea that this PDF is part of a network designed to redirect users, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://smidgel.ru/uplcv?utm_term=gk+questions+in+tamil+pdf PDF link annotation
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcbd76dc15---dojubomumofux.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/37645075068.pdfIn PDF document text
    • http://nicolalazzarotto.com/userfiles/files/zewaxewonutunedagin.pdfIn PDF document text
    • http://sumtinathholidays.com/admin/uploadfiles/file/zovofekerusekewi.pdfIn PDF document text
    • https://atlaskvartir.ua/data/uploads/files/juwigopidilotek.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210909194954.pdfIn PDF document text
    • http://ladna.pl/user_images/file/tinadefavesevusum.pdfIn PDF document text
    • http://lienming-rubber.com/uploads/files/202109052110585779.pdfIn PDF document text
    • http://erainbowrealty.com/userfiles/file/weledade.pdfIn PDF document text
    • http://bixenony.com/userfiles/files/38073728648.pdfIn PDF document text
    • http://energo-winstal.pl/userfiles/file/63831130844.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/zizutevazerolezopedof.pdfIn PDF document text
    • https://protrialse.eu/files/files/60791313765.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/mofolerewubedi.pdfIn PDF document text
    • http://nepalbestcargo.com/userfiles/file/90625122624.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/66421321264.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/rimup.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/47713309489.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/c1588d4b0c9c72fbd071244a82388169/kigerosirupimodin.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/bozukobusanexasup.pdfIn PDF document text
    • http://manuale.aziendasulweb.it/userfiles/files/38770402796.pdfIn PDF document text
    • https://debcopharma.com/userfiles/file/48292396169.pdfIn PDF document text
    • http://finance-bulldog.cz/UserFiles/File/33701306901.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/penog.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_off0000f0d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D7 20272 bytes
SHA-256: e2da5466c4b40edfbd9a2059099de524b802483fcd79f7c35a5a68882363dbb4
font_01_sfnt_off00012688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12688 10936 bytes
SHA-256: cfc9bf685684e54b1ede7fd04f67973011f428ef73723c7ba455acbc57a8f9ee
font_02_sfnt_off00013fb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1