Malicious PDF — malware analysis report

Static analysis result for SHA-256 b53ce2b6ed768725…

MALICIOUS

PDF

81.4 KB Created: 2021-09-09 06:50:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: fbbd562d218b59e89b08e649e0f5eb75 SHA-1: d9a5b5a1b844951a96699c67efed5aa64dc208ca SHA-256: b53ce2b6ed768725bd59de5995d1c1331460fec37fa5da88724e689de587e059
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is a PDF containing embedded JavaScript and numerous external links, many of which point to other PDF files. Heuristics indicate a browser extension installation lure, a common social-engineering tactic to facilitate malware delivery or credential theft. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or trojan distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://songhongresort.com/img/files/87804948108.pdf In PDF document text
    • http://www.humillacionyestrella.org/ckfinder/userfiles/files/13549144844.pdfIn PDF document text
    • http://abwlondonblvd.com/uploads/files/83945019917.pdfIn PDF document text
    • http://zimmerei-possert.at/figiz.pdfIn PDF document text
    • https://travelworld.ro/userfiles/file/jitexibedogelusewe.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/48757248421.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/87466713691.pdfIn PDF document text
    • https://youkuvpn.com/upload/files/pilabipufovuritidiluravuv.pdfIn PDF document text
    • http://bbfrontedelmare.com/userfiles/files/71358080448.pdfIn PDF document text
    • https://btegypt.com/file/14795725154.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/49097097565.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613732c2532d6---99665544277.pdfIn PDF document text
    • http://ms-beauty.com/ckfinder/userfiles/files/guxomuzumewogetajodeme.pdfIn PDF document text
    • http://temple.mo/userfiles/file/jajibetomepusenadifowi.pdfIn PDF document text
    • http://myucpb.com/userfiles/file/vutud.pdfIn PDF document text
    • https://dananeye.com/uploads/files/202109010224494631.pdfIn PDF document text
    • http://apple888.vn/luutru/files/57902081409.pdfIn PDF document text
    • http://stsmcc.org/www/js/ckfinder/userfiles/files/serafigazudirev.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jenevixisole.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/dulimudopanidaramojak.pdfIn PDF document text
    • http://kepco-group.com/uploaded_files/userfiles/files/wafapumi.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/52727818484.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/41694877144.pdfIn PDF document text
    • https://hoongnau.com/upload/files/zetufakepokesugiki.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/91377291671.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/xikomonunitovanifa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+block+the+website+in+chromePDF 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_off0000d937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD937 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF149 17756 bytes
SHA-256: c7cd69a0ac38656b8aa060d9b49034af20b792a0c42731a305dae0306ee1d1ad
font_02_sfnt_off00011f60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F60 10640 bytes
SHA-256: 6df2114b479b3b09c37cdd6a149de5582be5cc2f248544f5904ad264aaf7c272