Malicious PDF — malware analysis report

Static analysis result for SHA-256 33a807feb02d3fdd…

MALICIOUS

PDF

83.2 KB Created: 2021-09-16 16:01:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a478483df2694e172ead7ac39efbf3fe SHA-1: 7f5e8de292f5db747b0050e26b01ff4853051c4c SHA-256: 33a807feb02d3fdd66f628d912092a160f185031019915464bc815355fc5e5d1
174 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a browser installation lure and a download button, suggesting a social engineering attack. While no scripts were directly extracted, the nature of the PDF and its embedded URLs point towards a phishing or malware distribution attempt, likely involving a second-stage download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff20354cd2---sakisexiruki.pdf In PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/72237841961.pdfIn PDF document text
    • http://eakqshop.com/ckfinder/images_store/files/25231895682.pdfIn PDF document text
    • http://motolargo.pl/userfiles/file/pasegivoka.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210910223720.pdfIn PDF document text
    • https://paroles-vives.com/ckfinder/userfiles/files/94317735006.pdfIn PDF document text
    • https://bompentax.com/quangbasanpham/app/webroot/upload/image/files/loziji.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/xokafodapuno.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/jipulemenes.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/zepafudagerutaropijaj.pdfIn PDF document text
    • http://slhospital.com/upload/fckeditor/file/vasenuperarejak.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/30525110112.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/ac8be5d0eabe6dc465f88f371a6bc90c/jexikalekaxesip.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/vobuwenagisanoletalowijad.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/zidifomonobebewupasura.pdfIn PDF document text
    • http://omeofest.eu/userfiles/files/xulutixovalujas.pdfIn PDF document text
    • http://ort168.com/upload/ckeditor/files/maruzaseborotutowugi.pdfIn PDF document text
    • http://www.primariasantana.ro/uploads/file/faxeja.pdfIn PDF document text
    • https://oxfordjsr.com/userfiles/file/mimusugovoruwefejipuf.pdfIn PDF document text
    • http://photonart.nl/phpcmsys/file/zirutarisugibevusefo.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/kulugipalijevoxex.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/52537329894.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/faditokaraferowowob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=cara+membuka+file+excel+di+hp+androidPDF 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_off0000de6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6F 11084 bytes
SHA-256: 1ba9352ea40fc0745a7d7092d8d7d985b8f8ea811fc2fd2ecd08eb5318bd9417
font_01_sfnt_off0000f7c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C9 18080 bytes
SHA-256: cf45c7f92ca67a62487988554bf0fdb4a85b046e9e78f3037420fb96507d5d7c
font_02_sfnt_off0001270a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1270A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1