Malicious PDF — malware analysis report

Static analysis result for SHA-256 a93a3d94d42a6175…

MALICIOUS

PDF

72.2 KB Created: 2021-05-28 10:16:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 85461faa51edab68c6714f8d9787e5ce SHA-1: b6c467069145313c8c626b13188991835b69c5e1 SHA-256: a93a3d94d42a6175eeff268f3f08cb27d5e0d92108ca7f02ecbb6712d640276b
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains, likely intended to lead users to phishing or malware distribution pages. The presence of multiple compromised CMS upload links and disposable hosting indicates a deliberate effort to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e57ddc4a08b8abbb4cbe45b00e1d3966/68847755236.pdf In PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/4oo4voupa1np5qnrna873lsn37/xuduxesipon.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608374ed3c950---96501883024.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/9c6f055852d70b38c152d63f62a9f38c/1369115443.pdfIn PDF document text
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/68c1a2d247dfe9611d8b972d6d804208/2861183652.pdfIn PDF document text
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/oa1mp6kj6h81evngpadgd4r91c/97256004556.pdfIn PDF document text
    • http://ural-resyrs.ru/data/file/zesosamumotede.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e682472620---zogumuwez.pdfIn PDF document text
    • http://bukharaatlanta.com/sites/default/files/file/74487410802.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16073b7ca1122a---52737349351.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba83fce115---28733110323.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/57193201403.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16096131ebb1d5---1751473479.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/de0f7c69ad91a64ccb1fc3f68a780cb4/pemaxekagidizetin.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/e8bba8d9c6833ae1e35f31ec862b12d3/22351875952.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f87ed1f82e---88662690679.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=dna+the+double+helix+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4B 5064 bytes
SHA-256: f73f343db3038017f0d1adfe15035b7ca767f1c211fdee66a434218da3eb9a35
font_01_sfnt_off0000ef8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8A 10696 bytes
SHA-256: b13071dfe0025c3b627d78eead703b35aeecf335faae5075ab0cdddc7bcba92e