Malicious PDF — malware analysis report

Static analysis result for SHA-256 a068dbd0d2b74366…

MALICIOUS

PDF

80.3 KB Created: 2021-10-04 15:51:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8c0919326e8663c98328cee3ef2a6df8 SHA-1: f6f4d59a349ffe32a0e78a48f2f1c581d0fab29a SHA-256: a068dbd0d2b7436691890603739b9006deb7f2ec0e1932f76f7a5d568011f531
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 external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this, indicating the document's primary purpose is to funnel users to potentially malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://garglob.ru/uplcv?utm_term=the+salinity+of+estuary+water+is PDF link annotation
    • http://inphuduong.vn/upload/files/kitugogibideraligixubo.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/bivufanima.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/1880139617.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210908175538_g9ld0r.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/10421547299.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/78954082457.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/voloxebigutaxalejojiz.pdfIn PDF document text
    • http://iccarrentals.com/files/file/xemufesuterilo.pdfIn PDF document text
    • http://retrolondontees.com/userfiles/file/36231184530.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/duoarqe24ad1ibumbbjfoj1sj7/forurasegebenu.pdfIn PDF document text
    • https://shirbandifelt.com/userfiles/file/10104049908.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/a16g7cnd5j81f1lo220oaqa0rn/zulesodiwenenabom.pdfIn PDF document text
    • https://lp-tracking.com/userfiles/file/1851845125.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/47160520202.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/pesoferegujesawef.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/70823594389.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/lotesef.pdfIn PDF document text
    • http://polenes.cl/userfiles/file/55508059024.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/161404368dc483---77802425015.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/5e1851159eb08f386754cb1da5e25ee1/52230184309.pdfIn PDF document text
    • http://laclonghotel.vn/upload/files/fujor.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_off0000d392.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD392 10572 bytes
SHA-256: ac21cb227de620c2ad2b3b84275fcb836fdbb6c37d3b54cb03f1ca74c067cabb
font_01_sfnt_off0000ebbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBF 18484 bytes
SHA-256: 0111c8d6c5e7a6129e2bb8c179bd790bb2915ed95810f79c53e2d196daf82276
font_02_sfnt_off00011b9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B9A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1