Malicious PDF — malware analysis report

Static analysis result for SHA-256 904c86e02820c20e…

MALICIOUS

PDF

75.2 KB Created: 2021-06-11 02:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 0cb2b7f9f522bda92b6b223965a58482 SHA-1: 8a6a00bf4d652293d11867e304b63e1a082ba30c SHA-256: 904c86e02820c20edabcf6976cb0aba2cd89e17b491670e7bbde8e98af72b853
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to compromised websites, suggesting it is part of a phishing campaign designed to trick users into downloading malicious files. The presence of a 'download button' heuristic further supports this. ClamAV detection as 'Pdf.Phishing.Trojan' confirms the malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=nemesis+service+suite+download PDF link annotation
    • http://aimic.com/userfiles/file/99047215248.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/26524720463.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/zofem.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/u9fhaer8k52ovs781v6g2qms8d/tejinenifeduwudakawe.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d8dad647c---3414937032.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160abf265e8b87---33895007951.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8264ccae3e---31723592879.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/sezefos.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a44c046b3---10221576893.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/5h64pu1d1tha2fae2c8dufmii2/sapegafevonif.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16093d1fcd4fb5---zojewavelalagunigogegama.pdfIn PDF document text
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/070512bf8c69e5eedbed1d6f53a69ea9/jujegesabumumekivido.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/iuvle195f7hd614e99f8kpdrt2/35438792338.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1609718fde83cc---61625997348.pdfIn PDF document text
    • https://aspirans.com/files/file/detelosirewu.pdfIn PDF document text
    • http://fairway.cc/images/blog//file/pewobatu.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_off0000e992.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE992 5204 bytes
SHA-256: ad27259b6859d2bb611ba475cba162500088572e98233d54ce0f90e24cd9b01b
font_01_sfnt_off0000fb47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB47 10720 bytes
SHA-256: 6a339fa67278934ead9e5956f77b2ad47f1313addefe816612e2a30c22f617e5