Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ca03fb53e7b3874…

MALICIOUS

PDF

98.8 KB Created: 2021-09-02 15:17:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9a6346813685fbb37002b152ddbe1325 SHA-1: aabb2b05317c3d6f95f0369de802a0da4ae05b08 SHA-256: 4ca03fb53e7b3874090caf48f36cec01126e0e4ce7ff497ffe90b839570f8407
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with many URLs pointing to compromised CMS upload directories, suggesting it's designed to redirect users to malicious content. While no scripts were directly extracted, the PDF structure and link farm nature are indicative of a phishing or redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9875

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://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca4f87de52a---50596861950.pdf In PDF document text
    • http://newdimension.su/userfiles/file/sojugidavepig.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777afa08804---14424732055.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/42779562028.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/061ac0943cb136a727a63e98cef90101/nuripeturanogemi.pdfIn PDF document text
    • http://lovepetclinics.com/file_media/file_image/file/88033048485.pdfIn PDF document text
    • https://arerp.kr/data/file///gunenavoxiwuzidefodavox.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/161239c429d859---80213192931.pdfIn PDF document text
    • http://taxilitomerice.cz/ckfinder/userfiles/files/26116082296.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dd8ff26147c---67028913283.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/e1b9925d66ba0c4f3b17fff279d79d2f/36547814533.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/p5b6nc7jtome6r4fef0p8b29n0/zawomotode.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/xafegisizulatosijufa.pdfIn PDF document text
    • http://pokemom2.com/uploads/files/xinivo.pdfIn PDF document text
    • http://proxima-design.cz/files/file/fagote.pdfIn PDF document text
    • https://pasifikendustriyel.com/userfiles/file/junigivifitibizaxafapumiz.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f81f135f03---wizidopitoseloro.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/98022332572.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/74d8b3960d3abd93c83fd2e0fc33278f/pifamapi.pdfIn PDF document text
    • https://rajaunited.com/contents//files/fegaxadalipe.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/60595e0cf2890fabb250c13761b3ac42/44896401400.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/4c6e10c73347416a3a5e24ac72c851fe/xowobojaxusovowegono.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/57364714534.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c76fea891c4---namaforugisazusamikiji.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/zinosiveja.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021072500415773499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=architectural+design+methods+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_off00011b5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B5F 11148 bytes
SHA-256: e89b965d5194d10cfe246d9a58c35f6309aa39ec1f0a15a5c9cc5ee33848c3ff
font_01_sfnt_off00013505.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13505 18268 bytes
SHA-256: 9df20d31cff970d5ec764d7b4d19c439091ec37edb759b48d607efe2f68455cc
font_02_sfnt_off00016511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16511 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1