Malicious PDF — malware analysis report

Static analysis result for SHA-256 0091bd6c5ac909fc…

MALICIOUS

PDF

69.4 KB Created: 2021-09-13 17:20:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: add2eaba3e4b834b56e0371cb9d1238c SHA-1: 3192ee1f8c6d71cb6ea63eb906bd83c3443a7785 SHA-256: 0091bd6c5ac909fc7644babb5ec7a0d0a68d233e82f980799faaeeb3351e0ee8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicative of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://neonatal-surgery.ru/userfiles/files/54468815247.pdf In PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/wasiwaxonovolota.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613952ebb8fb6---guwusawaf.pdfIn PDF document text
    • http://findusafranchise.com/files/files/pusejoveb.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/70967949486.pdfIn PDF document text
    • http://lateonsettay-sachs.org/userfiles/file/medexal.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/17364075102.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/kigarovuwon.pdfIn PDF document text
    • http://napiarsaigh.com/images/29027070608.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/revimoxufadeneb.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/b2a96a6cb073bfdb429a9594a94d26ee/poxitupomitaj.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/vexirudifizogixitosupepi.pdfIn PDF document text
    • https://negaratoto.com/contents/files/relegujeb.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210910140857.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/39421756342.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/fixejukenowedewadivevuse.pdfIn PDF document text
    • https://pragatitic.org/ckfinder/userfiles/files/41605295788.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/nonapawopuvuzonabewixudo.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/15261070392.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/64504184651.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130fa5046315---77026460086.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210913064347_0gnyoj.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/vegumirowidu.pdfIn PDF document text
    • https://www.vita-organic.eu/admin/ckfinder/userfiles/files/zuseminepexajebubeli.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613292f11e4db---gogavuxetuxilojegimalo.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/11732754818.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=idle+defense+mod+apkPDF 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_off0000b444.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB444 14752 bytes
SHA-256: 9deb052c3a97203edddc941218fbe726c5344780e1f611f76622f73f3b60957c
font_01_sfnt_off0000d8ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BA 10412 bytes
SHA-256: 61dc72df7b2a2da140ad64e0b715eed1702dd5a9d0594a92e67f77e48c97803d
font_02_sfnt_off0000f04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1