Malicious PDF — malware analysis report

Static analysis result for SHA-256 91352c0bbd859073…

MALICIOUS

PDF

82.7 KB Created: 2021-09-12 02:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 418c80cbc6b4994773e4cbd7f5dd8d8d SHA-1: 766890e36d5818714c151807b391be31766bdf92 SHA-256: 91352c0bbd8590734fa0a26f226b20a6b451fd8864d5c09e5f008750f1258c41
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with malicious documents that may leverage embedded JavaScript for redirection or further exploitation.

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
  • 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=run+windows+program+on+android+tablet PDF link annotation
    • https://caror.hu/ckfinder/userfiles/files/mogovusaxumutinafobulureb.pdfIn PDF document text
    • http://pomodorolennep.de/gfx/userfiles/files/wogip.pdfIn PDF document text
    • http://xn--12cf1djdb6cbcafdbu1f1cudgcc8am4wf7htgd9de.com/ckfinder/images/files/baxaromiwotujinonigivewup.pdfIn PDF document text
    • http://ilkjv.com/Images/Media/files/77685909681.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/73441833868.pdfIn PDF document text
    • https://snowcat.pl/admin/ckfinder/userfiles/files/25428368603.pdfIn PDF document text
    • http://uklearningnetwork.com/userfiles/file/29491259734.pdfIn PDF document text
    • https://jmbarrenetxea.soinuenea.eus/files/galeria/files/4565767735.pdfIn PDF document text
    • http://artsar.pl/userfiles/file/77709532924.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/c09b8231d8991317172171528ed9b49e/wudakikaxox.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/c8d656f49cf3f8d4b256a7566f7995ad/dalavisanasawabi.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/5603712391.pdfIn PDF document text
    • https://excellencetogether.com/img/files/file/fewote.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/19948294340.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16135c8712fe1d---dodusezojojiwofugavunos.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcc4098eb2---fajosinarazajabo.pdfIn PDF document text
    • http://teresachild.com/upload/files/53089772259.pdfIn PDF document text
    • https://camelcarpet.org/d/files/79280536589.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/e3c97e56d293405beb6f8c56f7ce5bdb/nosogafuzukexusumelulux.pdfIn PDF document text
    • https://xrtradingfeedback.com/cmsimages/file/zedidij.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/towavifasiwaf.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/3a9960518252e5de6b2883827ec4a9a9/podebakamuwuwumunel.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee1c0da047---4012665318.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/48490194988.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/gowoxorupuwazolenuxudu.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_off0000dd0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD0F 17816 bytes
SHA-256: 7210d51b510d2e89d89aad8273af1fd02bf0067c6508eb3adb2c4018d0f731b0
font_01_sfnt_off00010b22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012339.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12339 11104 bytes
SHA-256: d98e7121d0ac3b1be618576fbe134f88185a41e9eaeaeb6a71b1f71523738903