Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fa5b9821cf31234…

MALICIOUS

PDF

72.4 KB Created: 2021-09-13 07:12:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3a565b485b7e8a6809c0323f4f70ef69 SHA-1: c8b521ad55c8bac3c60ab121c0cf32dd7b7b7e89 SHA-256: 3fa5b9821cf31234b124f3eb16a1ae127fd8a5a8cf0ea969f7cf288968e72320
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a common phishing lure designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://catamma.ru/uplcv?utm_term=3d+car+game+apk PDF link annotation
    • http://squash-fitness.cz/userfiles/file/migusobi.pdfIn PDF document text
    • http://tuderprogettazione.it/userfiles/files/18179521876.pdfIn PDF document text
    • https://thuanxuongmonmb.com/admin/webroot/upload/image/files/tanuj.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/90206527262.pdfIn PDF document text
    • https://curewelldiabetes.com/userfiles/file/19935158541.pdfIn PDF document text
    • http://srilakshmienterprises.net/uploads/nivadeloji.pdfIn PDF document text
    • https://shopexpert.com/app/webroot/files/userfiles/files/57045145458.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/malaperuzufejozub.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131183012c7a---14611493247.pdfIn PDF document text
    • http://folientastaturen.pl/_data/file/noviserejozukaw.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/83209280736.pdfIn PDF document text
    • https://carlojans.com/cms/file/jukote.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/31318707078.pdfIn PDF document text
    • http://songpinhao.com/userfiles/files/42883756916.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/vugetelitu.pdfIn PDF document text
    • https://funbugs.ie/userfiles/file/5760131506.pdfIn PDF document text
    • http://salamatekhanevadeh.ir/ckeditor/files/files/22211023990.pdfIn PDF document text
    • https://www.hkha.org/ckfinder/userfiles/files/gazesipu.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/69362555257.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/nozadesujigetojem.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/sukejopezutipavex.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/ot1khtonbccskmp1q3kpq7irv5/jumofoxejakapum.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/lizetaxizaluja.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354fecc1ab9---1036114265.pdfIn PDF document text
    • 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_off0000ba84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA84 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d296.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD296 16276 bytes
SHA-256: f4e4a39016d435f9f9fdb721bff3954c9c54fbc22316c979f6c60ce0c4a50548
font_02_sfnt_off0000fc75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC75 10396 bytes
SHA-256: 284ba99898d2c4c640767968b8ee1f8c14443465a4df2b9b124b176a29cb747e