Malicious PDF — malware analysis report

Static analysis result for SHA-256 99fbd5685dad02d1…

MALICIOUS

PDF

79.4 KB Created: 2021-05-02 16:12:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 8f5cc81a0caf2b940d9b54acbd9c0ac1 SHA-1: d4fd27c254def027553c4aee1f49f6f57248ad4f SHA-256: 99fbd5685dad02d180c5b3067e559186f9cd5e3a182a7e2ded0e75ab64be7ded
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to lure users to malicious sites via these links.

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://www.nuyew.academy/wp-content/plugins/super-forms/uploads/php/files/cc1a609e73a1ce4e522cb22676e5743d/39269908896.pdf In PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f99c145bdd---68425256236.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160726b8ff26aa---pititutolofuja.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/40c593496fcb8a8571329dde5c342549/67290575713.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/a9b94ac72adcbcbc7c52f246ff373fcb/fotowijekawikini.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/23cnpr4h2d24c9gmmp4hhpaqn6/dusexipapidogakebalefe.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/7hoijct5cbk3ceu0g4tjis704c/63996984638.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce7f6c5b27---katorifutenupo.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608118f54d8e6---zuxewida.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/4962bc749daa595c079a2b9610f21512/70438089638.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608990eab3031---47355721934.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16075e9a4c0223---92028557191.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/3b318a3cb2409b53ce3c3a0f6f1ed979/43888687908.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/2843543195fed52e3d6c29c56de2b07c/32988345672.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/a6a200217a6e111a673c8647817b8b22/51831495485.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/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=livre+d%2527+algorithme+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_off0000f5ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CA 5312 bytes
SHA-256: a91759bdf5d68df8d1c60b7313975dd8f3e3940278f6c395eb4b8560d44a6fe9
font_01_sfnt_off000107c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C6 12760 bytes
SHA-256: 7d643d3deac82f0cfd99d52307b6602f4da4ecd79771496459af72d7f97aca19