Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff9b6e814fcee865…

MALICIOUS

PDF

79.4 KB Created: 2021-06-11 21:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: ac7d14d511355ad5edcdcef21f42f19f SHA-1: ff2ece3524d56ef80070161f002e2566ebbf3776 SHA-256: ff9b6e814fcee8654022e5f8e0cab1e2aeafdb084ff9748b651e77923cf5100e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, with high confidence. It contains numerous URLs, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, appears to be a lure related to 'sheet music', and the PDF structure indicates it's designed to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nomylo.ru/uplcv?utm_term=four+seasons+summer+violin+sheet+music PDF link annotation
    • http://szkolka-wiercioch.pl/files/file/48344323805.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/69018184012.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/pivareguzewinop.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb2b489a77---20049540642.pdfIn PDF document text
    • http://poorclarescork.ie/images/17940179718.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa56add9851---73917779405.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/94b798a9a685dd02e6336b5d80253cc7/34267189992.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097d6a1a6865---mepomirekokomelebizo.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/ba9a1f84b3bd81e156d0d577cf4c2367/41266586562.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a86859db1d3---23633267342.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d7dc12a12a6b6fca45b1d12974b2d5d8/magutato.pdfIn PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/5ecdriu610suq7bcb7km372lgi/40314295086.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607a43378eb47---41254451716.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/329bdc6d5547ff3322d830cdb91d3559/lulelunirazapexur.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/3950ccf8d1c463f607ae981e07387671/wijepasej.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF804 5056 bytes
SHA-256: 1d3e157e53271678db335b621b2d19d7f19aef2ea411d4c78d2a22f7b3cc0ca2
font_01_sfnt_off0001090f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090F 11152 bytes
SHA-256: 7f714fa0f18936788c096b3b30b38610d7f34d9a1e989c539be00a3c4ea35262