Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ff65d5fa5a68e89…

MALICIOUS

PDF

79.0 KB Created: 2021-09-03 21:28:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5820f53d957463025ef1164e9d63fb62 SHA-1: 433b053c7163a9e1e1206f2d47a338b6b188f18a SHA-256: 8ff65d5fa5a68e89cf0762170ca71ac5e603603a751d9578f3bb86a40ca6c212
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to other PDF files hosted on compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/eefa021420462585a4d92d39525ce29e/wefesejaruwedadid.pdf In PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f0678754840---xixejugubeve.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/ad248a455d382eab8940c2bfb391ccc9/47924960070.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/gitifilozitikefut.pdfIn PDF document text
    • http://xsteelstock.com/d/files/pikevexi.pdfIn PDF document text
    • http://naucseto.cz/storage/41390911566.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8658c05ba5---fomozudolozaf.pdfIn PDF document text
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/33368667700.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16086fde6c17be---254365631.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/16226579172731.pdfIn PDF document text
    • http://jlm-kg.com/uploads/file/77403070763.pdfIn PDF document text
    • https://bdcomunicazione.it/file/fupasigegum.pdfIn PDF document text
    • https://artbynela.com/uploads/file/61159235538.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/vedipo.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160942744b0051---wojeposinasifojo.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073df7db7560---solakarosivowanetonuzez.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/zulalapukukojibif.pdfIn PDF document text
    • https://soalmatematik.com/userfiles/file/gadoxaxojufibedavenofevi.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116d693e616c---75625222184.pdfIn PDF document text
    • http://mhspartan79.com/clients/9/97/97d0d0788ec4d6723ba7be3cd58769e3/File/32643524277.pdfIn PDF document text
    • https://nffcd.org/userfiles/files/69238308063.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/81059730209.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/gidawidamesexobat.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/7337373522.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160d4ecc4e30b6---jebabogaw.pdfIn PDF document text
    • http://auapp.ch/userfiles/files/fulebaxulox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=%C3%A7al%C4%B1ku%C5%9Fu+pdf+ink%C4%B1lap+yay%C4%B1nlar%C4%B1PDF 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_off0000ced2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCED2 18608 bytes
SHA-256: 4678c65e64d69e083f0ec91c84516a841652a1789d6599c8d326352866b1a44b
font_01_sfnt_off0000fbd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD7 10676 bytes
SHA-256: e0fc9f4db9684e951ca6a8d6541873398ea362461468009f831892653c8b075a
font_02_sfnt_off00011412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11412 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1