Malicious PDF — malware analysis report

Static analysis result for SHA-256 0704def94852163b…

MALICIOUS

PDF

82.3 KB Created: 2021-09-08 15:34:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 29acb088f87bd7bc7f089a762f309ba8 SHA-1: ed49f4c95bd0c37c1ac19603487802183f5c5b55 SHA-256: 0704def94852163b5ba76ff56a21473ecd0cce848f1ad35b85d6b3b17d4500fb
126 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier. It contains multiple embedded URLs, with one heuristic specifically flagging it as a link farm on disposable hosting. The primary IOC is the URL pointing to a PDF on ovstav.cz, which is likely the malicious payload or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ovstav.cz/app/webroot/files/files/33680429861.pdf In PDF document text
    • http://thanhnienxp.com/vietkiendo/upload/file/17913488518.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/batigurodaxide.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353752a6aac---44065111143.pdfIn PDF document text
    • https://bda.ch/ckfinder/userfiles/files/96451542348.pdfIn PDF document text
    • http://camara.acessoainformacao.org/uploads/ckfinder/files/tikamokozibodetugodubejes.pdfIn PDF document text
    • https://shindah.com/images/ckeditor_img/files/xosisi.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/72607141079.pdfIn PDF document text
    • http://xn--80aesyq.xn--p1acf/files/file/zoguwuvaremegedasogizo.pdfIn PDF document text
    • http://cdkuysuujk.handysociality.com/upload/files/58546226435.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/murexijojudexepafukovova.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/20050164350.pdfIn PDF document text
    • http://i-dron.cz/data/file/94054808684.pdfIn PDF document text
    • http://domario.ru/userfiles/file/ludiwaranowinofoga.pdfIn PDF document text
    • https://polresseluma.com/assets/ckfinder/core/connector/php/uploads/files/xugujexe.pdfIn PDF document text
    • http://topimmigrationlawyer.org/ckfinder/userfiles/files/94297896127.pdfIn PDF document text
    • http://alotercuman.com/ckfinder/userfiles/files/86091453951.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/loxopurup.pdfIn PDF document text
    • https://altstudio.be/app/webroot/uploads/file/51812310076.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210902223716.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/25206327390.pdfIn PDF document text
    • http://jsushibrea.com/uploads/files/fajewuvigutaduribujagi.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/73750450284.pdfIn PDF document text
    • http://atrsara.ir/resource/files/jizutorepenib.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/32917655141.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/36407208613.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=star+wars+colouring+by+numbers+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_off0000d942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD942 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF159 11480 bytes
SHA-256: d27f4a06a7361d5c20ffad8f37e0d28e58a43f92ada84ff0e8eecc50a8d77df7
font_02_sfnt_off00010c21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C21 18432 bytes
SHA-256: 11a152fa4324572ea2cb3f60ede948701afd66b33a8b928b6b915b6fed513ec7