Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5d92d7b397f93c9…

MALICIOUS

PDF

103.0 KB Created: 2021-07-22 02:18:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e5929ef6ae4970cfd7a991f6f360ab49 SHA-1: 32fb6394bb6e6adf604b483da31327dc5c75d2df SHA-256: e5d92d7b397f93c9fb704e4c532f80d9d967939baaaa1f44c5c6b38c9e4f8b83
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV both flagged this PDF as malicious, with ClamAV specifically identifying it as a phishing trojan. The primary attack pattern involves luring users to potentially malicious external sites via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/3q45l6eer5lomh7fk7cfpeu5ca/kepotisewivimuwedubobex.pdf In PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/39491bb0f13faa0673fec1f83a9f5211/40047403266.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/dilodadewadol.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/boxalubiliguk.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd81c0279f---78460321529.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/11479623736.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/lasepujuma.pdfIn PDF document text
    • https://giga-tronics.com/userfiles/files/zeraraxo.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/79a00a542743b581b9b2bd0d87b18966/91547672464.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4985536c7---jojakekurebifidaxum.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/f333086019651950daa7f766a2e8b195/nitulaw.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/zodakopaxoguvikozej.pdfIn PDF document text
    • http://falerisztika.hu/tmp/20567240481.pdfIn PDF document text
    • http://amblesidewindermere.ca/fckuploads/images/file/vozoboguzakegukojemu.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/nvtnundrdlvhivcjgqtksstppo/86163159826.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/pulogivaginus.pdfIn PDF document text
    • https://dascalita.ro/app/webroot/files/userfiles/files/2083489182.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/nawavusebezegosigap.pdfIn PDF document text
    • http://vtaky.sk/media/file/pekavipakewifibib.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/68238613893.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608381644fbc9---liramevivelusezonelufe.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bb3760eadc6---47125786056.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609a4c4caff4a---wetisijusal.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/823aeb3fbadeac57cef5f598d4c71676/70371945865.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa7fc3af28---fisovitugirejifus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=college+lecturer+jobsPDF 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_off0001307c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1307C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00014893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14893 10448 bytes
SHA-256: c00c1ea440b93d3a18f17a1da0c156c585d107a82bd9b899d24e529776cdfbb1
font_02_sfnt_off0001607c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1607C 17204 bytes
SHA-256: 02e8e19976d9895ad1fe116b508fb898d359df763607dd068a0afc525232ed92