Malicious PDF — malware analysis report

Static analysis result for SHA-256 5644f00ea3e8e420…

MALICIOUS

PDF

97.2 KB Created: 2021-07-29 17:31:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 395fe3d795ec5fbfafdd35db833553e1 SHA-1: 50bc9c10e5b753ef42dffa16c104d2331e9d519e SHA-256: 5644f00ea3e8e420c8d30177099af52866e318c943667d1eb63e5b920adfe0f5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The primary attack pattern involves luring users through a seemingly innocuous document to external, potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9889

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://dorrstrechy.cz/UserFiles/File/vedulonunal.pdf In PDF document text
    • http://gerd-pollak.de/userfiles/file/78842239370.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/53478747942.pdfIn PDF document text
    • https://publicbridge.pl/userfiles/file/gefokodariwigilubisosedon.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/f8p3ncrf6nfj4i19e3goa0etih/luzasijomukur.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609df3b406156---98763430737.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160da4d8508265---momevotatever.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/40028106361.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/04f2fb3cdd2e70d9dfab6725b26fd9d5/pujovewu.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/98789409159.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1fc2eef0e---zuwobowixiw.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4b7c2ada5---lejakeviwutit.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b1aa609de5c---nedakanagomak.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/8du9vblh6mbftorv398nlrdq03/22188473779.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ba71d6556a7---12172983675.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160af6d8359af9---88226272852.pdfIn PDF document text
    • https://bloomeng.com/uploads/21201143512.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087621809011---37436345590.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a35bc8e675d---10121044486.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/9af0844be802a705bd5b5d6ccaae97cb/22461003123.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/95384581309.pdfIn PDF document text
    • https://stvorki.ru/files/file/diborovotiwunabemoxitedu.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/vovoni.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/bekezazipedudaroki.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a92b97c0209---diditizukok.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/79616505353.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/51785163798.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/ascqkerirfdjn0jcqji7pg40mn/kepivoxaru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=narasimha+swamy+stotram+in+telugu+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_off00011244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11244 18172 bytes
SHA-256: fe7971f46dd3375ef3c28bf96d23145ce9aa7a5b48fbf419cb56367cc812aee3
font_01_sfnt_off000141b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000159d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159D0 11220 bytes
SHA-256: f0f8f17e94415b662dd506a10a7a16d3c92f468914b35a33e5234ba6a4e7bba8