Malicious PDF — malware analysis report

Static analysis result for SHA-256 819bcd0a746c5ff8…

MALICIOUS

PDF

75.1 KB Created: 2021-09-18 08:29:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6c926296ea249b4c469e96811b28502b SHA-1: 2d81d04c8a2fd5da06609cf2562814161afc6d82 SHA-256: 819bcd0a746c5ff8b9039687efb807afe394c5da39044069a88f79be8dae0158
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of a link farm hosted on disposable domains. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious content, disguised within a PDF document.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://metallpress.ru/files/45177763078.pdf In PDF document text
    • http://ambulatorioveterinariorigolon.eu/userfiles/files/vovuzogiruvovirirewos.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/12739911867.pdfIn PDF document text
    • http://dreambeauty.kr/upload/fckeditor/file/17580602131.pdfIn PDF document text
    • https://tdemo.order-pro.com/ckfinder/userfiles/files/86986841894.pdfIn PDF document text
    • http://opakowania-loga.pl/zdjecia/fotki/file/10796603759.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/gizikokibenowubeleg.pdfIn PDF document text
    • http://dfanchem.com/upload/files/likolopirutimeweseki.pdfIn PDF document text
    • http://anais.terminarz.online/kosmetyczka/krakow/files/4497603348.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/zavuzakirutojozivuk.pdfIn PDF document text
    • http://haiannweb.com/uploads/files/xikemelotisotej.pdfIn PDF document text
    • https://homestayhoian.thamtuddt.com/uploads/image/files/sodulabopakatolimowamopi.pdfIn PDF document text
    • http://tnmetalworks.com/images/files/dowusitikovituropuwu.pdfIn PDF document text
    • http://stavo-bazar.cz/userfiles/file/turojube.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/93522320200.pdfIn PDF document text
    • https://drddvichitra.com/userfiles/file/11191603444.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/vq97oeu2i2u6nk829rljskprmo/26685066245.pdfIn PDF document text
    • http://tgroupsrl.com/userfiles/files/41455820225.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rokutani.pdfIn PDF document text
    • https://mklaassen.nl/images/file/zutavaritabibulapulovo.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161427ccf4cb47---89363834841.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/4f241d13a0325e351bbc2625ebe4bdea/15474437358.pdfIn PDF document text
    • http://detskaoptika.cz/ckfinder/userfiles/files/nogosogafuruvajovedo.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/lipijadukubu.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/xemisudemogizufikux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=fucosoft+android+data+recovery+crackPDF 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_off0000bfc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFC0 10772 bytes
SHA-256: 6e412723e48cf4606ee1d74349b56dfa5aa55f286c835916290410877124ded3
font_01_sfnt_off0000d8b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B9 17856 bytes
SHA-256: 19587efef6b1d61851fc07f0f3d54557843ae55e3d415dcaa0c1e04bec34c0ff
font_02_sfnt_off0001066f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1066F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1