Malicious PDF — malware analysis report

Static analysis result for SHA-256 5353d876a7b85802…

MALICIOUS

PDF

67.1 KB Created: 2021-03-23 09:24:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: f7f3ba7ce5031bcae393cbf8b6465f1a SHA-1: 85a80f96faf8b77f2b01f6e8857b20a43891b30e SHA-256: 5353d876a7b85802b8428d1b9f273c1c91bfa9038ea2242e9384b6f088347035
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

This PDF file contains a large number of external links, a technique often used for SEO manipulation or to distribute malicious content. The ClamAV detection and ML classifier strongly indicate maliciousness, with the PDF being identified as a phishing trojan. The embedded URLs, such as zajinet.ru, are likely part of this malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://zajinet.ru/strik?utm_term=ejercicios+resueltos+de+probabilidad+y+estadistica+para+ingenieros+pdf PDF link annotation
    • https://wisapemewe.weebly.com/uploads/1/3/4/7/134713478/supalidodij_jidof_pamabo_wupogemiboton.pdfIn PDF document text
    • https://cdn.sqhk.co/noluxokeruma/iejchiP/vinifadadutow.pdfIn PDF document text
    • https://cdn.sqhk.co/gepabafi/Fasidig/strategy_tactics_ussr_vs_usa_mod_apk.pdfIn PDF document text
    • http://wuzidifefomir.iblogger.org/ketevigasugetuzebujovo.pdfIn PDF document text
    • https://wedutigumufezeb.weebly.com/uploads/1/3/4/6/134659425/jabefeg-zawokatub-xezuvonugine.pdfIn PDF document text
    • http://nazomomomujo.iblogger.org/allan_poe_historias_extraordinarias.pdfIn PDF document text
    • https://cdn.sqhk.co/rubovadu/gHRjdib/sheet_music_the_dance_garth_brooks.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb6fcc27-0f66-4833-9aca-f468ba71bf5f/the_forever_war_dexter_filkins_free.pdfIn PDF document text
    • https://434dcbc4-7bd9-40fe-99bf-e102daebf961.filesusr.com/ugd/07ef24_5e6fa8618ed74693bbedb4f635a71ed4.pdf?index=trueIn PDF document text
    • http://suvoxezol.rf.gd/chrome_extension_ublock.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de0f2906-3cbd-4595-8884-e0b57c3f5737/r_programming_tutorial_for_data_science.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/19154c7e-89e9-46b7-823f-9a48a3aa30a7/how_to_identify_liftmaster_model.pdfIn PDF document text
    • http://zilokujidetomo.epizy.com/detelirewasil.pdfIn PDF document text
    • https://45dcde1a-aed5-4138-b95e-a0f768a283bf.filesusr.com/ugd/89441e_1c4e5841335342fa9ca688c2eb3d4881.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c4ec2f5-d4b1-4c7a-9e2b-8d41669b6ea8/how_to_find_probability_without_z_table.pdfIn PDF document text
    • https://6db1e9a2-4282-4636-8d41-de07325ad911.filesusr.com/ugd/d97b38_b6db0cf0909b40bb9187d320ce7e2703.pdf?index=trueIn PDF document text
    • https://486bfeb6-87d8-40a3-812f-3449909c9139.filesusr.com/ugd/81b904_a8cc49e2aa0c4d22bcd95eb5531ca962.pdf?index=trueIn PDF document text
    • http://tozegebefile.rf.gd/grid_paper_template_excel.pdfIn PDF document text
    • https://5c2cca0d-3a4e-48b0-93bf-8ac6c0c026cb.filesusr.com/ugd/271e65_c1158a304219481e93f4f73bacf83399.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8115f32d-8217-4b4a-af75-7275bf9452bb/41504725811.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_off0000c7d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D2 5600 bytes
SHA-256: 3c01802b09586225720ba595359049cda84a061e529463ceeca3f8d6edb07a7c
font_01_sfnt_off0000daf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF5 10936 bytes
SHA-256: 59703375ccb29f4484e2943ccba72fab79777f40e0465e822a74157c05f9f949