Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c936288eb88880c…

MALICIOUS

PDF

72.8 KB Created: 2021-06-01 18:32:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: fb0bea8a1f9e3982b9a33f4046caf3f9 SHA-1: eaad4b3d5732f01ae0fa64d9118cef0ee5c17861 SHA-256: 8c936288eb88880ccad736616067e8c6a4fe0220accdeaef08d90ec7f4034ec8
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised CMS upload storage, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to exploit users via deceptive content.

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 http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/8furrafc74cmh1ok99dbdvefo6/gedupofaluko.pdf In PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/9e157c139029b3cd0c44df06df58718e/kugefodijuw.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ced0a862f6---10397035183.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/mariko.pdfIn PDF document text
    • https://consultingexpert.eu/fckeditor/userfiles/file/balixuweboxoguve.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/bo81jfqff3i78h9r38r2lifhuf/35643592524.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/omvtr6cacjndp237i9789o32mm/15345078127.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/cba8268a45edfbc1edf1474dedbba96a/23830452328.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/namuzakowatokufafetiguxo.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16076a328f2923---11612775088.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160afdea425e32---sasafem.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609541c010886---gaxagabibawofagapitiv.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160742b24cb413---72950199410.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/91238797902.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca6291e89d---rakama.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/gv16o7mhsqllujvt2e66hr81ss/1874326928.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/lozivanakadesukefut.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/~3/1xuhb7AK25c/uplcv?utm_term=how+to+remove+links+from+a+metal+watch+bandPDF 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_off0000df3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3D 5576 bytes
SHA-256: 1a50c96bb52cc26eeab2d2ab0d65aa3ea8b1f3ef3622b7def204591dcbc8f6e4
font_01_sfnt_off0000f217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF217 10676 bytes
SHA-256: 6d8c223e1537cf48d61122454c49d5b19dadba4eb30012afc8579e7253222397