Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfb8192edd1df80c…

MALICIOUS

PDF

80.4 KB Created: 2021-09-08 16:53:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 84d0d4cbe236d8b7fed00fc3dc974e42 SHA-1: f8308f9c332d40c67eba8a395222746c608c6d33 SHA-256: dfb8192edd1df80c18470808b99add896f186d38b724dc96721a72950eac7588
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and link farm heuristics point towards a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://laborke.ru/uplcv?utm_term=converter+dwg+en+pdf+gratuit+en+ligne PDF link annotation
    • https://beta.nhatthiengroup.com/files/uploaded/files/lenejixim.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/detezapulomuditomul.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/podatefudekopik.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/23787890364.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/9f91dd5e13d83c67f4b6feace7ee208b/61774572252.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/8723281051.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/51964649170.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/zuwurevajin.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/83075492756.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/jirezo.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/161300bcecdc94---ronekudi.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/wojoxarojitazabir.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/19639268210.pdfIn PDF document text
    • http://2rent.gr/userfiles/file/xetofesoned.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/46259003962.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202109080648215969.pdfIn PDF document text
    • http://klick-tipp.info/ckfinder/userfiles/publics/files/tiwitatomizijugirafi.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1613681ebca514---gafapujokawavarefepemomip.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/025gig8gljq1nqllg2n8s5es30/dakese.pdfIn PDF document text
    • http://specialcats.nl/media/files/pipak.pdfIn PDF document text
    • https://0924055971.com/uploads/files/202109041519269937.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/4461279486.pdfIn PDF document text
    • https://autotronics.vn/userfiles/file/7201193753.pdfIn PDF document text
    • https://ijieet.org/ckfinder/userfiles/files/86813430250.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/zizimagum.pdfIn PDF document text
    • http://tagsu.com/attachments/fckattachments/file/67271926697.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/runavabu.pdfIn PDF document text
    • http://irodori.kir.jp/files/file/95584807434.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_off0000d606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD606 17072 bytes
SHA-256: f483e4fce34a5cc258fe28bdc291e5e445a5db234dd77f3fc5b54f23370ed712
font_01_sfnt_off0001015e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1015E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11975 10788 bytes
SHA-256: 133058f4fe5824dc809a168b7af8eccb3502a94904fd592fb784c96b5bf87b5e