Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bcb85d21ece7cc0…

MALICIOUS

PDF

83.9 KB Created: 2021-06-10 05:33:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 9e01869d0fc1bc9e09ec3197ad7039b3 SHA-1: bc0ccf1b7b872966e6c1d97fd9f1424989515007 SHA-256: 4bcb85d21ece7cc09dfbd9ce76fa215031e9b7207297248aaddec3e46b0189b7
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://cructi.ru/uplcv?utm_term=mark+twain+nominees+2020 PDF link annotation
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086ec44350f7---59665229235.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160acd09a897df---falarodewavem.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b2b679e5a725d03640d29f6902a0dbff/tejifikutijipobugoned.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4235b4dcb2---57421549037.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3437493b1---nisoxaxesudiba.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/rtainbq8ooclkd60p8m4bnqb9k/tuwutawagijej.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f6a65512f---pesuxewegu.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/vukufitibozowisuwafomapo.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/kojini.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/8pvabit6uk053b5cjqv5e7m3u2/39974243686.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/vraibt613aifvlrd96moqccas8/xapadonomotido.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/5lc4v6hgokmjn24dbb67h8aj6r/30349864044.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/7c006b04a6de3cd39e0cde6f04240db3/37812858217.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/doduxulor.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/34ljmd9a7vne1neppn2927ofd5/luduwuzulalilidimex.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED8C 5236 bytes
SHA-256: 98b80dc429912e68e1beeda22e2e989f1e58ba1e891a96009175ba6e33087b81
font_01_sfnt_off0000ff5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF5F 14000 bytes
SHA-256: f81d55d64de9849ca54f6db58145b15797678c2a7a34e265aaed6fc1f7bf93e1
font_02_sfnt_off00012c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C26 16140 bytes
SHA-256: 1ffca1ef16be5e2ec436e77f9211a88ad3199dc781cb76600401cc2e2c7dce6d