Malicious PDF — malware analysis report

Static analysis result for SHA-256 d206f77dd582e905…

MALICIOUS

PDF

71.6 KB Created: 2021-09-17 11:04:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4a420a1f48eb5bc92561b43ca9df2ceb SHA-1: 45ffd56573157b2d4a754ad5dfdeabc0af7a7a4f SHA-256: d206f77dd582e905c5544e1472f31f7a4ed6ba36555fa54214d6313569b5fbba
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious actions within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to external URLs, such as the observed 'pistant.ru', which are often used for phishing or to download further malicious payloads. The sample's structure and numerous external links suggest it is part of a link farm designed to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://pistant.ru/uplcv?utm_term=minecraft+unblocked+classic PDF link annotation
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/jukowudebiz.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/vawibukomagujazuv.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/gepuxopa.pdfIn PDF document text
    • https://andhimazhai.com/images/files/panasimawumuvasilemigo.pdfIn PDF document text
    • http://medianet2000.net/amm_prod/image_news_popup/file/tulezinuj.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/mifanusatese.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/24235020692.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9eaa639e1---sagosixe.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/tabokuto.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16144201d223ed---wugubega.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/bijaxiduposofi.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16132c4bb03900---12568079891.pdfIn PDF document text
    • http://www.cpiequipos.com/assets/images/user_files/files/30276254791.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/74973883013.pdfIn PDF document text
    • https://togeltop.com/contents/files/gewaxoluperotetodaku.pdfIn PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/bapezorazafosolagider.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/sabovujovebe.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/10396478515.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/jidunafop.pdfIn PDF document text
    • https://nikunjfoundation.org/ckfinder/userfiles/files/wixanux.pdfIn PDF document text
    • http://acril.ru/ufiles/files/19861082243.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/benozibeviwebefo.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/xidisivodaxozilimawogo.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/duvopujipifokewiwujadi.pdfIn PDF document text
    • http://mcutech.net/upload/2021/09/file/1630951211126779284.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_off0000b893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB893 15320 bytes
SHA-256: 192002c2a311f03fa40f848e241b5c3310ac076c29a0af7605b3f054cc047471
font_01_sfnt_off0000df5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF774 10796 bytes
SHA-256: 990e9fd72a025c94da4d9358b163e9e9e296f2ffe94370183c56525a1bbb3599