Malicious PDF — malware analysis report

Static analysis result for SHA-256 973d4fc2cdf24c89…

MALICIOUS

PDF

86.0 KB Created: 2021-06-25 01:38:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: a8cf25cbbc6401a62a899b56292abffb SHA-1: 13a3ee47823d4d6e3afe55cc74e51566b112efd1 SHA-256: 973d4fc2cdf24c890bd01fc8c9fb80ba76db71185cb22ef4f815b3d677227aae
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to compromised WordPress uploads and other disposable hosting domains. While no scripts were directly extracted, the presence of PDF link farms and the nature of the detection suggest an intent to redirect users to malicious or phishing sites.

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://media-get.ru/userfiles/files/bukanodagagu.pdf In PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160802f6acabdf---kitinopitabatezudiginovuf.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/93dd16fa3ffbd554c902d930f0779cd8/sugijexeresuz.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/d272194a61dcbcaabdb87ec41e500318/keterurixev.pdfIn PDF document text
    • https://mfdesign.hu/files/file/nutatosuzonejizewodeposa.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/newolutiwiwererawuko.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5d012dfb1---73919265878.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/527c7ffd5c3823413cbcc955d4fdc269/tazujozugerepuvixodijefuf.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/44582978036.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/e6ae543b736b48f4b1340b5193c9f857/47497556082.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/82565126206.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083d1e6355cb---40862889529.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/07e14339d9fb0b22e689a40d2cc8848c/92838563968.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8f0b4288e---fewoma.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/nikuzogolimusare.pdfIn PDF document text
    • http://keacg.com/upload/files/lemeredazavuresatala.pdfIn PDF document text
    • http://bike-aholic.com/UserFiles/file/44531457191.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=buzzword+book+class+2PDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000103b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B9 4992 bytes
SHA-256: a663bb243898e1ba153e0ab4406c52598db529726a003888c164a0fa9ada0fdd
font_01_sfnt_off000114d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114D3 12312 bytes
SHA-256: c839b730ef6710079b0565887023d04651870ec1464b044b0b41854746efb37f
font_02_sfnt_off00013d46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D46 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f