Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b8630acf7deab1f…

MALICIOUS

PDF

69.2 KB Created: 2021-06-24 14:29:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 4b78bff6082944aa65b038332ace8128 SHA-1: 46f07c393b1b9def3ac680b1e751a23c027cefbc SHA-256: 3b8630acf7deab1fe4d2b52861d9024682fc5c3eea01e9a6e05e5bee9a59edd0
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a machine learning classifier and ClamAV, indicating it is likely a phishing or malware distribution lure. The document contains numerous external URIs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest it is designed to exploit vulnerabilities or trick users into downloading further payloads.

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=iste+standards+pdf PDF link annotation
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/16111c322f4d04b3b77f26ebfbed839e/xivowod.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/83686147370.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/33588b4c438e46d7f21f28f6d349300d/43232767606.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160b4940f8af97---beveruluwamujalizopaf.pdfIn PDF document text
    • https://serviceservice.eu/userfiles/file/xudekakuzukojenowi.pdfIn PDF document text
    • http://gfhs1978reunion.com/clients/56625/File/26606061605.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2e034bc8d---62168793211.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210616163702.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b21f8d4481d---kijuxitudazetewebivan.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160999fde954b4---69909317740.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a68d9d2e297---63678427758.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/eed9cbfb7fb736a4ea7a19ca9a638416/rurijonumek.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609025d8960ff---79070276544.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/japeduneminagevoj.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/nilomaninafiga.pdfIn PDF document text
    • http://bronia.org/userfiles/file/90459535700.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_off0000d1fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1FE 4940 bytes
SHA-256: ade8e9f21472db183830ca8df4ca7ace1f6d5b47511a749d987efbbaf8b22146
font_01_sfnt_off0000e2da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2DA 11088 bytes
SHA-256: f5a787f3b0340ee024a757e14bfe980c09b465aa85445b79253ad5122979d2da