Malicious PDF — malware analysis report

Static analysis result for SHA-256 0ac6b9952baf207d…

MALICIOUS

PDF

83.9 KB Created: 2021-06-03 00:18:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: c282cb3b058f8f3d6306e606274f7c79 SHA-1: 8bc5d46d086c0312edcd70f5d2194dc3d8aa510d SHA-256: 0ac6b9952baf207dbe81be263d6249fc18ebfe1440b550d50e649b6585ec6663
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or malicious content delivery attempt. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to potentially harmful sites. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, which is sometimes used to create malicious PDFs.

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://coretry.ru/pbw?utm_term=is+nano3+a+base PDF link annotation
    • https://mafewesoxadix.weebly.com/uploads/1/3/4/6/134697647/5260925.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426974/normal_60678a08e9051.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385617/normal_5fdf34017dc94.pdfIn PDF document text
    • https://jeboxuxu.weebly.com/uploads/1/3/2/7/132710743/4954613.pdfIn PDF document text
    • https://kuratiwupojaxu.weebly.com/uploads/1/3/4/0/134017491/lurilaputonekanowige.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425255/normal_6007eecdd8221.pdfIn PDF document text
    • https://libazuzed.weebly.com/uploads/1/3/1/4/131410812/7023217.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4463825/normal_5ff593b9c9fb5.pdfIn PDF document text
    • https://nujunilotup.weebly.com/uploads/1/3/4/6/134642651/fc6d2b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476123/normal_60142dfb1f1a1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456728/normal_60212bd58157c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403260/normal_60586d17c007e.pdfIn PDF document text
    • https://boviseweduxiraz.weebly.com/uploads/1/3/0/7/130776594/tusekukirowi_leden.pdfIn PDF document text
    • https://lepabamun.weebly.com/uploads/1/3/1/6/131636917/xivirewewa-kejek-zigonenovo-pelalokorak.pdfIn PDF document text
    • https://navolujute.weebly.com/uploads/1/3/1/4/131483334/7844245.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384299/normal_604f735d6a9d3.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4419637/normal_60b0a27be55a0.pdfIn PDF document text
    • https://kizegugiruliti.weebly.com/uploads/1/3/4/7/134729255/zojemevexujopiwali.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://werinenimuta.pbworks.com/f/pauvre_anne_chapter_4_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6f0579a-2694-41df-9953-711512ac742e/how_to_convert_a_word_doc_to_on_iphone.pdfIn PDF document text
    • http://zufumegi.pbworks.com/f/73324544059.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e68dac11-7c11-496f-8573-7fb640115b01/73730321649.pdfIn PDF document text
    • http://xodelow.pbworks.com/f/animal_hunter_unblocked_games.pdfIn PDF document text
    • http://ruxafonan.pbworks.com/f/how_do_i_turn_off_private_mode_on_samsung.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off0000f9e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E2 6492 bytes
SHA-256: cf6bcbaf462759e04676f8989e7e87ed4d43c4317550ddbd0c5684ab0bd17b73
font_01_sfnt_off00010a16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A16 4792 bytes
SHA-256: ac28e85c929b0d7247913ed25e9804c6cbfa56a35e19e8206aebf0367ee1f3f6
font_02_sfnt_off00011a77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A77 11804 bytes
SHA-256: 509c19575473388fef0e968d5f59caddf2e69187c5e2654f7d676e5ad4d1bcaf