Malicious PDF — malware analysis report

Static analysis result for SHA-256 542237d219b402d7…

MALICIOUS

PDF

76.2 KB Created: 2021-06-23 07:49:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 071d99a4b05cd91467ecb55c17954329 SHA-1: 00b55d3f479cc24d57989edb620034c584001779 SHA-256: 542237d219b402d7f7593a23aeeb7badce0d4550aa65aa443b404f2869623354
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-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 https://krisoc.ru/uplcv?utm_term=nccer+contren+learning+series+answers PDF link annotation
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7ff14a99d3---nanejiso.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1e8869193a---65619564720.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b4948a31ec4---74809463422.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4a7e479f9---10201504802.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/airkmv0va8dpur2bsd179pou91/32438887063.pdfIn PDF document text
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/d5fe6bbf7a9f93ef1fba20e13d00e2cc/2674775305.pdfIn PDF document text
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/3601883d49d59c70cccf29156c022382/71329993958.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c48cbe5cb---zizusakelu.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16094d6907c79d---18776301061.pdfIn PDF document text
    • http://maternites-catholiques.org/ressource/site-image/files/moxisanedezuda.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/vl8400c9fseobadnk1sq1ul4tu/56234148762.pdfIn PDF document text
    • http://ahsaipu.com/v15/Upload/file/20215131323599826.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ed470209a3---xunuzomebigonazerepor.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92977ae76f---maravixekavirareberax.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608456cf4479c---33400524360.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/4ae3151cd7dcbb887bc4c8c13cf41490/73417127429.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_off0000ea87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA87 5028 bytes
SHA-256: 17fd267681671bf3bcc7ff0816e7d84f29c3dc1cf8a4a67f7ed143bb68674556
font_01_sfnt_off0000fbc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC7 11816 bytes
SHA-256: 4769aa4faf9aa94e36237c09117fcf6a1b0e8fef4c3dfa08d19194b56cad7a15