Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a6327a7c15d4c20…

MALICIOUS

PDF

70.4 KB Created: 2021-09-12 12:17:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cf57d33c730a1772da91c7dc91cbeeb1 SHA-1: 3e066e132d7fc6bc36cc4aa6b3e4759c4c9b111f SHA-256: 8a6327a7c15d4c2044f21a1f091267b0f2f1757b2b8f8b0cd24bed22d1ed37fe
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm, with many URLs hosted on potentially compromised or disposable domains. The presence of these link farms suggests an attempt to direct users to external malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://radiosmile.hu/upload/file/50873019053.pdf In PDF document text
    • https://daynexweb.com/upload/ckfinder/files/tozijurigojemanexu.pdfIn PDF document text
    • http://travelshops.pl/userfiles/file/99397884942.pdfIn PDF document text
    • https://chambres-lannion.fr/userfiles/file/sebakamidifejudoduriz.pdfIn PDF document text
    • https://5uempat.com/contents/files/majurirumiluzadogevator.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/panotape.pdfIn PDF document text
    • http://duocthientam.com/uploads/ckfinder/files/vegoxopaxe.pdfIn PDF document text
    • https://equalland.com/uploads/File/muribemegubozumob.pdfIn PDF document text
    • https://whatshoulditcostme.com/userfiles/file/nufikivu.pdfIn PDF document text
    • https://hijaustabilo.com/contents/files/febujuw.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/a4de4e51b329ce72c84f9f3cc8c81970/69661557402.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021090715095424.pdfIn PDF document text
    • http://serenetour.com/image/upload/File/pinuxu.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/tixapanijeb.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9e7d1a4cc---rujotogisebufoliniwod.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b02f94a4b5---femikefojivorekexefe.pdfIn PDF document text
    • http://1careglobal.com/upload/files/70275128525.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/20168752236.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/63437155024.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/26021706901.pdfIn PDF document text
    • https://lighthousemacau.com/html_upload/file/bazosirajenesezetupumu.pdfIn PDF document text
    • http://esen-life.com/userfiles/file/malarusoguwajufiwu.pdfIn PDF document text
    • http://togclick.com/media/userFckfiles/file/54725294570.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=android+messages+for+pcPDF 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_off0000b42f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB42F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC41 15520 bytes
SHA-256: 12852be7f173bed3f13764aae5b9fb4e579ea2f20c1ad8e50de048909aededca
font_02_sfnt_off0000f377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF377 10800 bytes
SHA-256: 543a1b31ac3dd0984b85a64f86c87f8322ba097491aadb3b8519fe6a66b74ae8