Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e8503f9c9c9ee8d…

MALICIOUS

PDF

83.0 KB Created: 2021-09-06 09:59:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: df03db92393fbe1a81fef7a90ffecfa4 SHA-1: d26c927eb12ba89fd0287d11f58af4b8db49b1ea SHA-256: 9e8503f9c9c9ee8de2e50f95e6f9f88667a550cfe7892e3bfcaaaf421df98a5e
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious content. It functions as a link farm, presenting numerous URLs that likely lead to phishing sites or further malware. The presence of compromised CMS upload links and disposable hosting suggests an attempt to obscure the true origin and purpose of the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://krisoc.ru/uplcv?utm_term=bebras+challenge+pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/bv5502oj66fqbk1q1bsgdqp306/42870179495.pdf
    • http://portalkucharski.pl/app/webroot/media/files/79495389224.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160961240104fd---xobazu.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/756e85981173f03b33e30448e12358c8/wuxukowozarogududet.pdf
    • https://educhina.mn/editor/files/jebajuzeridejufuxaniwes.pdf
    • http://tt-ural.su/admin/ckfinder/userfiles/files/90980678439.pdf
    • http://peoplefoster.com/pliki/xafajigopavifawaripuluvo.pdf
    • https://healthmatters.me/userfiles/file/jusosoxasazanivawafeworo.pdf
    • https://shiokuda2.com/contents//files/sizoveget.pdf
    • https://people11people.gr/uploads/File/kefobufokurozopesu.pdf
    • http://tries.cz/media/images/upload/file/pesumibekegedekij.pdf
    • https://cnn-logistics.com/asset/files/95757588510.pdf
    • https://pelletier-tp.fr/ckfinder/userfiles/files/62741719538.pdf
    • http://www.siscbolivia.com/admin/uploaded/fck/file/82572821226.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/1ol5g87a5dq3p6gudin0bj56q3/mumitolavimufi.pdf
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/popomomoximemopezo.pdf
    • http://digifast.cz/userfiles/gigojajudegigun.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/fff7592ca0496450909c28cc9e41c46b/33551168463.pdf
    • http://agendatourvietnam.com/hinhanh/file/zamotajutebiba.pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/cum67hv5pk56gifnc7fmv8ev0j/zawekajo.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088e8820824a---31909022239.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c416539b4ab---mogiwasofibejenotixir.pdf
    • http://dwhs79.com/clients/15834/File/beduwusoxubugomati.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/92un6rhtth123d68jfogauh1ns/34670303688.pdf
    • http://beloezoloto.ru/userfiles/file/93876101603.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c535f8d68f5---natabilunimazokuri.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de31.bin
dd46cb6f515dd8b92a8491a95048a61eb64e78e122f1f5fcd91e043657237e27
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE31 10784 bytes
font_01_sfnt_off0000f689.bin
44c316362d50eca7c6cd7c21e9888e44284eb3b8eb1ba477b92136857aeef2d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF689 18324 bytes
font_02_sfnt_off00012628.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12628 16792 bytes