Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fa0a8b915b8d503…

MALICIOUS

PDF

77.9 KB Created: 2021-03-26 05:43:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 8e4152f900147b2c08988256e0aeb73e SHA-1: 5b963626589017fdd0529325e63cdb8a9d2246a5 SHA-256: 9fa0a8b915b8d503d2e6f02878165327a15c99d2bb435abb091844b57252d6fe
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains numerous embedded links, with at least one pointing to a known malicious redirector (https://yafferge.ru/wix?keyword=connective+tissue+worksheet). The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is part of a link farm on disposable hosting, suggesting a phishing or malware distribution lure. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the embedded links are the primary indicators of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 4

  • 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 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/wix?keyword=connective+tissue+worksheet In PDF document text
    • http://ruwemipuwev.mypressonline.com/principles_of_cost_accounting_vanderbeck_16th_edition.pdfIn PDF document text
    • http://likefetevu.getenjoyment.net/creative_sound_blaster_z_vs_sound_blasterx_ae-5.pdfIn PDF document text
    • http://dejepuzalew.mygamesonline.org/mutton_biryani_recipe_in_telugu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0a3c8164-ddd9-4522-8472-457ce31ece15.filesusr.com/ugd/d32f78_a4b9bd624b2640058509dc4acba5b99a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zinudipir/dragon_quest_xi_walkthrough_gamerguides.pdfIn PDF document text
    • http://fibafewupo.epizy.com/time_management_and_academic_performance_of_working_students.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8685308-f7ed-454b-96e1-ba4199ae6f8b/61876028031.pdfIn PDF document text
    • http://bitenozof.atwebpages.com/socio_economic_and_caste_census_2020_report.pdfIn PDF document text
    • https://c4cd0dbc-23d7-4f11-b65f-2561cec8abe5.filesusr.com/ugd/516793_e3ba66435a7d497487d2a527c6c96150.pdf?index=trueIn PDF document text
    • https://8271b8e8-1520-4b18-8785-2fafc8cd33e6.filesusr.com/ugd/efc97f_603bb7e2b776429daa6506cc722507df.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/28d96a29-08d3-441f-bd96-6e416757e8bd/13482181054.pdfIn PDF document text
    • http://juwukopegonamu.onlinewebshop.net/wupiribivarawid.pdfIn PDF document text
    • https://s3.amazonaws.com/fekazudabo/carry_on_maratha_movies.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30bb163c-64aa-449f-b97a-bbf75553f1ee/basic_maths_formulas_for_5th_class.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7510e579-c532-4522-91c4-a82feab395e8/adobe_premiere_pro_cs4_tutorial_for_beginners.pdfIn PDF document text
    • https://s3.amazonaws.com/fezenur/kodujenilepelopuxakinulo.pdfIn PDF document text
    • http://fopopas.epizy.com/right_angle_and_equilateral_triangles_worksheet.pdfIn PDF document text
    • https://459ec6dd-5b69-4322-a182-74abbfaa0e48.filesusr.com/ugd/221eaa_59392d86e8eb48a79714cb0050096e37.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/patotale/wazexakupewil.pdfIn PDF document text
    • https://s3.amazonaws.com/punurum/how_to_fix_shop_vac_motor.pdfIn PDF document text
    • https://36425c1f-c329-48aa-845d-1f8252cb45c8.filesusr.com/ugd/01d500_04047a56355f42a79f02da2570aa48f0.pdf?index=trueIn PDF document text
    • http://runuwug.myartsonline.com/madotefezofeleka.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ce2ef67-bce1-46bd-b9f7-49d4344ac7fb/what_are_some_examples_of_cloud_computing.pdfIn PDF document text
    • http://wipadafefuxasi.onlinewebshop.net/44972245938.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_off0000f4e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E9 4768 bytes
SHA-256: f48ee0d5051bf91bc87780534a942b7e94ec19037806270f8fcba59a856ff932
font_01_sfnt_off0001052f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052F 10876 bytes
SHA-256: 4575db1273502075671a167ee6cbe30b62fbd268800aa8466ccb4e9705ee7328