Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca7835c00fa31b65…

MALICIOUS

PDF

75.0 KB Created: 2021-04-18 07:40:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: fbac3d5db2fbffdcf18b2eed6d2c81e9 SHA-1: 2ce4dfa3abec5d289eb5c60ff337339db94ec15c SHA-256: ca7835c00fa31b65eb6cc2c4e98cd45e7b861f434b5bfc62dafd7e4f22d35d05
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic confirm the document's purpose is to drive traffic to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://pelibifir.ru/strik?utm_term=miller+bobcat+225+welder+generator PDF link annotation
    • https://dofenerezi.weebly.com/uploads/1/3/4/4/134446603/7245734.pdfIn PDF document text
    • http://sdfsdfsdf.shaketorch.com/promega_transformation_protocol.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418197/normal_602fbc3874ed4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496577/normal_5fdefa319e671.pdfIn PDF document text
    • https://taxajoberaruvu.weebly.com/uploads/1/3/4/3/134320235/f2599.pdfIn PDF document text
    • https://zipakodexosif.weebly.com/uploads/1/3/5/3/135344546/65d83443f159e.pdfIn PDF document text
    • http://fiwudowa.22web.org/what_is_the_history_of_job_in_the_bible.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471692/normal_5fee91396596d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417122/normal_60433b8871360.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419192/normal_5fcc4e31a33c7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xogegusubo.rf.gd/cheng_man_ching_form.pdfIn PDF document text
    • https://855e1e5b-0daf-4dce-aa73-dfad2bfec5df.filesusr.com/ugd/ced2dc_93f3035f0bba4c679ac62a1552ef8bec.pdf?index=trueIn PDF document text
    • http://zikapoxev.epizy.com/grade_7_maths_term_3.pdfIn PDF document text
    • https://77bac38d-831a-46d6-8f22-d7743fcadc58.filesusr.com/ugd/5b9a87_a3f59328a0244daf9889fc9682277c1b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muvarelo/how_to_fix_my_pdp_xbox_one_controller.pdfIn PDF document text
    • https://s3.amazonaws.com/vobuturinivi/vitiwezejo.pdfIn PDF document text
    • https://5862e4ea-63a6-4c92-af93-e06d02d1a664.filesusr.com/ugd/eaa371_43c21a7d65f64a2e9fc05cc36a756316.pdf?index=trueIn PDF document text
    • http://jekutekovemimav.rf.gd/lonoginosugalak.pdfIn PDF document text
    • https://s3.amazonaws.com/sorogamat/bombay_dyeing_online_bed_sheet_shopping.pdfIn PDF document text
    • http://dovobol.epizy.com/canon_rebel_t5_manual.pdfIn PDF document text
    • http://duzoweserunojoj.epizy.com/20390673117.pdfIn PDF document text
    • https://5c90cfa9-af55-48e2-9430-1f3580382729.filesusr.com/ugd/e2b09b_6feee1157fe14617ba1e4a88518c6ea7.pdf?index=trueIn PDF document text
    • https://9f53eded-325d-4e02-8430-7c09bd872488.filesusr.com/ugd/e04405_513185b322ce44c78211e1b9b67bf0b5.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tajimipojimo/40529313295.pdfIn 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_off0000e50a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE50A 5424 bytes
SHA-256: 5961b23c472eac6d90acf375c8a5472aac3468eca6dd8a52c10cac676337f4ba
font_01_sfnt_off0000f7ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AD 10976 bytes
SHA-256: 79ac16f5ae11c2def85a82f4b9ab11adfd00bf1f8b4d9f1675065b45275c218e