Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a6a0239ea998b9d…

MALICIOUS

PDF

72.2 KB Created: 2021-05-19 07:49:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: a0d64395fe6aaf489dc38352c81df70f SHA-1: 2923ba52ca2490b70c2a453db56a314ad8030ad3 SHA-256: 8a6a0239ea998b9db284e529179fcf5d7657cc37fa7b58c07472cd3de8dd1638
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 domains, suggesting a link farm used for SEO manipulation or to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and external link farm behavior are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://ponafet.ru/strik?utm_term=preliminary+for+schools+trainer+1+answers+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4471481/normal_5fc5bde7de096.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4474739/normal_5ff93de57dc49.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420760/normal_6018e2e3d17a2.pdfIn PDF document text
    • https://gagufamuxolo.weebly.com/uploads/1/3/4/7/134748057/8303942.pdfIn PDF document text
    • https://loribipusav.weebly.com/uploads/1/3/1/3/131379532/374336.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404528/normal_5fda2b1d9331e.pdfIn PDF document text
    • https://lufodeku.weebly.com/uploads/1/3/4/5/134586195/a48ff6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481820/normal_604ad293cffe3.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/06eea1cb-8789-4791-9857-d5f42df976bc/how_to_train_your_brain_into_positive_thinking.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1be94a4a-d0b3-4bc8-aea5-2bd65691e7a4/punuzakipu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/113b0080-1cd5-4190-a6ae-4aaf8721690f/hp_laserjet_p2015_symbols.pdfIn PDF document text
    • https://s3.amazonaws.com/gedexim/what_is_the_top_rated_shark_vacuum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dfbc85db-3b98-4412-9dcb-e0daae363ab9/17047594571.pdfIn PDF document text
    • http://zalaxorenisev.epizy.com/winning_chess_strategies_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db7043f4-b84f-452e-b546-82524d429cba/hp_probook_4530s_specifications_i3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d21a3baf-4a4e-4d79-9693-31db00a86894/yummy_cookbook_recipes.pdfIn PDF document text
    • https://s3.amazonaws.com/punurum/wixuratupugole.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/01d609da-7699-4525-bf47-a0b5ec9c7315/how_to_change_time_on_sony_dream_machine_icf_c414.pdfIn PDF document text
    • https://s3.amazonaws.com/widuxade/81938654771.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a7922e1f-5ab5-428e-acd6-f2baf7952cb6/niveles_de_prevencion_de_leavell_y_clark_vih.pdfIn PDF document text
    • http://mutodilevo.epizy.com/certificate_of_compliance.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8477a844-36b1-428b-823c-7d047e3b330b/how_to_setup_wifi_on_my_chamberlain_garage_door_opener.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_off0000da0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA0E 5640 bytes
SHA-256: b51b9546631c63245a0b47593d1944bcf5350a22914154c8f91d5a55952e6025
font_01_sfnt_off0000ed31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED31 11688 bytes
SHA-256: 161a3339c1b6608b640295436ff6d106a727d3fe500bc87eafdcf55fecb54359