Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bd8911b86cd6fa1…

MALICIOUS

PDF

76.0 KB Created: 2021-06-23 23:47:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 94d8b48229fbecb215457ac648e994f4 SHA-1: 50f9a62e38cdbd1013025713c0caadca531755ce SHA-256: 5bd8911b86cd6fa17607bbb1eb13935fbc95967c7812ad02c7e7aac5a05adc35
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076fc6f294f2---geger.pdf In PDF document text
    • http://rydelko.pl/userfiles/file/13577777982.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/nukafex.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093b1f4aa468---vilinebepiwebunixu.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702e498458a---71504226804.pdfIn PDF document text
    • https://lasanisports.com/files/tosofifoj.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074508ebcd81---77232871038.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/c8b71b318a80309a42c1498a32b998b1/mipolanetoxamuvugoselas.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8afd8911ed---40939703903.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607074d47615e---nikuvixesodudolamig.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/a33952b90ea72ae7257d3ed7d4ae2fc8/21982215782.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/5199d555b8f6edb86d71814b9a22300d/sejagopuxa.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092beabb5c27---79095916253.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/nepofagigo.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/pufavelitojar.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/~3/1KS0DP0cxss/uplcv?utm_term=camino+real+tennessee+williams+script+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_off0000e8a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A8 5296 bytes
SHA-256: f096e469ac74a73c255aa5e5dbdc30e19fd569fec6c0c7fe7655e9bb55f633c9
font_01_sfnt_off0000faa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA4 11284 bytes
SHA-256: 1367e3a6d196c3b04d2113560bcd155d82001869360aae20485d00042fafdb6a