Malicious PDF — malware analysis report

Static analysis result for SHA-256 518dec50914c74a2…

MALICIOUS

PDF

86.4 KB Created: 2021-05-31 20:55:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6c3bf127b3258babb13d0eea7d8a81ab SHA-1: fc7e0f5cb802bbae4e3915c8871bda71e91e74f5 SHA-256: 518dec50914c74a26c9da983d0d0253da56bd3c42c10a5a388862310cd29bd6f
244 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains a large number of embedded links, many of which point to disposable hosting or redirector infrastructure, including a link to `https://yafferge.ru/123?utm_term=carl+jung+red+book+free+pdf`. The document body is heavily obfuscated and appears to be a lure for search engine optimization, likely intended to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=carl+jung+red+book+free+pdf In PDF document text
    • https://romudakon.weebly.com/uploads/1/3/5/3/135318284/1289487.pdfIn PDF document text
    • https://rigasalimuf.weebly.com/uploads/1/3/4/7/134703392/3432674.pdfIn PDF document text
    • https://sugabora.weebly.com/uploads/1/3/4/3/134369176/luxulemetuz.pdfIn PDF document text
    • https://gafekiwukuwemul.weebly.com/uploads/1/3/4/3/134313713/megowiboroxejupul.pdfIn PDF document text
    • https://senuwisaf.weebly.com/uploads/1/3/4/0/134018119/19b6a.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/4cbbf412-829b-4181-aabd-334791130021/what_not_to_eat_on_keto_diet_menu.pdfIn PDF document text
    • http://viluxese.pbworks.com/w/file/fetch/144423540/recommendation_letter_for_kindergarten_students_examples.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28bd04ea-267b-4155-bb34-0b7f82f4792a/vw_service_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1257d9a2-91b8-4e10-bf93-34654817c4f9/motorola_symbol_mc9190_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/177b70bc-d08e-41d6-9b7d-703bf7bbf759/76764241920.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/60c5511e-c895-4ea7-9ca0-411cfb6e2134/cinderella_story_book_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e08457c-2fed-4a0c-b277-8871efb21f9d/interesting_facts_about_langston_hughes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/083d8129-5ae1-491f-8d55-209dd04554dc/market_wizards_by_jack_schwager_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26be978a-df02-4eb5-854e-bacc9d948dcb/best_free_subwoofer_box_design_software.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6953e2fa-75e9-4483-a734-1f7b3512f8b0/what_are_the_two_visual_strategies_in_organizing_information.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7e834e6-1596-4b4f-8c9f-df0ef859bce2/roald_dahl_boy_-_full_audiobook_with_text_audiobook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c381f00-e9ca-4a35-a6b5-67ceb06b15f2/what_is_the_plot_of_a_rose_for_emily.pdfIn PDF document text
    • http://lekuzax.pbworks.com/w/file/fetch/144419193/new_products_management_crawford_di_benedetto.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7eb514f6-3e08-490d-ab83-bb1303dfe8f8/bangladeshi_baul_gaan_jewellery_kare_dekhabo_moner_dukkho.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4506629a-90d0-4f07-9ff5-eefa8cb7e0ca/les_contes_bleus_du_chat_perch_questionnaire.pdfIn PDF document text
    • http://xoxafepapesu.pbworks.com/w/file/fetch/144412134/99793606974.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/626288fa-7d6b-488c-ae12-03597dcbddeb/jemawuwisi.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10037 5216 bytes
SHA-256: 22c62cd967bee30379288da63d8c12ae0bb9fe89f0466db08fe34b0b39ae8ac7
font_01_sfnt_off00011208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11208 10980 bytes
SHA-256: d66e79e8d5d398f22e41fb083b0e930c3cbd9e1ac446669a4a9a723a6424558c
font_02_sfnt_off0001371e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1371E 16060 bytes
SHA-256: 503f5200e83b189a546b6c6e1d808633a9135186956fe76ff9bd78de3d91e3c6