Malicious PDF — malware analysis report

Static analysis result for SHA-256 385f5fe2174dd76f…

MALICIOUS

PDF

82.6 KB Created: 2021-09-09 00:03:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 56293203bd633b8d4197ddb6843a5a24 SHA-1: c424c7c2ccc77113b277c4e8a33b571bc00eca98 SHA-256: 385f5fe2174dd76fbbe79e6118a72ce5919cfb76f9ef05d2d11fb18ac853d399
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://coolbiotech.com/upload/files/viwawisodutegokeninezado.pdf In PDF document text
    • http://jingyilin.org/uploads/file/72904530395.pdfIn PDF document text
    • https://sudhirsachdevaclasses.com/ci/userfiles/files/72202676296.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/36549775776.pdfIn PDF document text
    • https://foulardfotografando.it/file/9260534101.pdfIn PDF document text
    • http://esistore.be/userfiles/file/99395722817.pdfIn PDF document text
    • http://hasyo.net/files/file/46833361813.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/82255433836.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/leberuledosuvozila.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312ce3c2a3c---61341808729.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/tuwubepirabasi.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/f80bca061dcef1882c9d988bd6b83053/datuvaxetufi.pdfIn PDF document text
    • https://bc2000.order-pro.com/ckfinder/userfiles/files/42768741570.pdfIn PDF document text
    • http://mesterteto.hu/userfiles/file/jevukabijuxuv.pdfIn PDF document text
    • http://wohntraumgmbh.at/vugelijatetixade.pdfIn PDF document text
    • http://hocomesun.com/upload/wejosoxupas.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/76291995605.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/83a0qo1mfosdo3vavijpp435j3/nuxafet.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/lupani.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/dasiwetim.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/butoletoxevepigirazira.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=weather+report+apkPDF 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_off0000d755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD755 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6C 10024 bytes
SHA-256: 2fbd4836c2af78ac3c22e781bd807de81204b5a294c8f7fcbe3828410a6f51d7
font_02_sfnt_off000105d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D5 21336 bytes
SHA-256: f47cfd1fae33fed4037c7b6bac073202674936a900b0038c20470c0bbfec6c67