Malicious PDF — malware analysis report

Static analysis result for SHA-256 b82714f0715df019…

MALICIOUS

PDF

87.7 KB Created: 2021-09-13 20:48:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 995a9ffb0c12c99421f5c9a7b1495a4d SHA-1: 7bacab0ba5c3d69d977d14030631de2100dd1403 SHA-256: b82714f0715df0193f2879dc985a222d12798dd204b452c11004ab4161c2a677
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is the primary function, likely to manipulate search engine results or distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://duszek-lasu.pl/userfiles/file/70446710036.pdf In PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133492ca1247---kefujigafitotez.pdfIn PDF document text
    • https://underworldgear.com/admin/images/fckImg/file/95852428982.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/zigotiloloxasimojida.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/sosojuzafoveko.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/wured.pdfIn PDF document text
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/xegazidaf.pdfIn PDF document text
    • https://ubranni.com/uploader/files/gawitorisajana.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/ritufamatuwidelawidil.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109131732567765.pdfIn PDF document text
    • https://castilloexterior.es/ckfinder/userfiles/files/talotapogafigusone.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/kipezixalotijaganowedo.pdfIn PDF document text
    • http://compufoxmail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/kigidefapuvifelipo.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/67656206388.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210907093150.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/xefupatunagewopafovigiref.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210901_AA33A7724F43BB40.pdfIn PDF document text
    • http://wyadonline.com/userfiles/file/13612463108.pdfIn PDF document text
    • https://viboot.com/ckfinder/userfiles/files/rivijilexukopaguv.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/51bedc23b1d3e65d36c99e9c021bf997/ruxosapavug.pdfIn PDF document text
    • http://jualumnitoronto.com/editor/uploadfiles/zozujimun.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/39765498056.pdfIn PDF document text
    • http://hdurmuslar.com/images_upload/files/88659127715.pdfIn PDF document text
    • http://appli-veolia.net/ckfinder/userfiles/files/32905712302.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/79229308743.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=dance+dance+dance+haruki+murakami+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_off0000ece6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE6 19852 bytes
SHA-256: a7a8566741b0fe36de445e63fade80812fdfc3410fc603bb04c238e735f42ab8
font_01_sfnt_off000120c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120C1 10648 bytes
SHA-256: 82f21de81b893dbf223b97a4b549e9056046f95d5e721817e0c621591574c4fd
font_02_sfnt_off000138e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1