Malicious PDF — malware analysis report

Static analysis result for SHA-256 4940ef63ba8bab9f…

MALICIOUS

PDF

82.2 KB Created: 2021-09-18 16:59:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b780739238ccf58d92b67979e33510eb SHA-1: f940cbfe2c3997c149843121370a639f4fa0232e SHA-256: 4940ef63ba8bab9fb7b470d9d1b7297d19a5d6b8b88a03a7f396f7f7a6f7ce17
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://wastran.ru/uplcv?utm_term=words+starts+letter+a PDF link annotation
    • http://vizugy.hu/uploads/files/files/90386401612.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/nujumi.pdfIn PDF document text
    • http://systempro.kr/userData/board/file/vimapuw.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/73050522186.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021091607475873499.pdfIn PDF document text
    • http://twtime.com/uploads/files/202109181523484702.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/motovovofumonowimuteterud.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/zojixupawovi.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/kesenojobanedefilabodi.pdfIn PDF document text
    • http://hosteleriayvending.com/ckfinder/userfiles/files/77060586998.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/jukaxoxevilitugizokefixe.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/lufatawumi.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/57553359475.pdfIn PDF document text
    • http://phutungototuanphat.com/img-tvdl/files/mivoromozivirowovanafeba.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613aecd34ffc3---72293763059.pdfIn PDF document text
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/260744274.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/fd8e3a7cea43e2cf13c5b974fb7f5d00/dikafanuvas.pdfIn PDF document text
    • https://perfecthospitals.org/FCKeditor/file/jefijalogixegiwanupokajo.pdfIn PDF document text
    • http://mauthietkedep.info/upload/files/67285582360.pdfIn PDF document text
    • https://gelblighting.com/userfiles/files/81078023791.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210903051143.pdfIn PDF document text
    • http://coiffurenais.com/userfiles/file/34065420547.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/zinofawevuloboxo.pdfIn PDF document text
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/kekusuruxudeniz.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/98479378034.pdfIn PDF document text
    • 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_off0000dea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEA1 10036 bytes
SHA-256: ca692bbb457b501436a0013c6f3aba81a468a318ceae1aa7a0b5258439646035
font_01_sfnt_off0000f51c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF51C 17748 bytes
SHA-256: 7cea175734abda56ad94e90f8f5c55bc9c5b4ccf54d9d5014092ce7bda2081c3
font_02_sfnt_off0001232e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1232E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1