Malicious PDF — malware analysis report

Static analysis result for SHA-256 3dc5402a1032a8d1…

MALICIOUS

PDF

71.9 KB Created: 2021-03-22 05:12:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 0f93301c2de772a9949f052f0fb52d70 SHA-1: 74157ac63d245ea04ec4793502dbd9194a0ff33a SHA-256: 3dc5402a1032a8d174463a4763d48deb8e6a6be884857a0fc6ad25f9e264e493
126 Risk Score

Malware Insights

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

This PDF document functions as a link farm, directing users to numerous external websites, including suspicious domains like jottigo.ru and rexonina.medianewsonline.com. The ML classifier strongly indicated maliciousness, and the document's structure suggests an attempt to manipulate search engine results or lead users to potentially harmful content. No scripts were extracted, but the presence of many external links is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://jottigo.ru/strik?utm_term=plot+probability+density+function+excel PDF link annotation
    • http://rexonina.medianewsonline.com/positive_psychology_study_online.pdfIn PDF document text
    • http://nakekizedexu.getenjoyment.net/manual_j_load_calculation_service.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445550/normal_60029664afb2b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450337/normal_602c82973e4dd.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/74c1d269-465c-4be4-a4a4-942b3335a766/how_many_gold_bricks_in_lego_harry_potter_5-7.pdfIn PDF document text
    • https://s3.amazonaws.com/xutomoxu/84530127014.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/69bd91e3-2476-47fc-992e-ec234f8c24d9/33829494714.pdfIn PDF document text
    • https://73a1781f-5c9f-4c76-8a11-a8e8c44f336a.filesusr.com/ugd/d9f7b5_9e98cdedff4e48e680241210677b02d0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/995e36d1-831f-4ad4-aaf0-fe4022795fbc/sugimu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0546d014-6230-4b67-90e4-9b873f05aaf0/39613726895.pdfIn PDF document text
    • https://s3.amazonaws.com/marimejerebo/how_do_i_turn_on_my_envirotemp_water_heater.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63b74e19-d7e3-4102-b469-565d302bc879/ysrael_junot_diaz.pdfIn PDF document text
    • https://0cc2a7d0-6f33-4335-9ec9-554d9418487e.filesusr.com/ugd/cb4a18_c500fbf4b19145e1ab0887e1d43887d9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/59d27c7f-4457-4e04-9f12-0f76fd110f81/battery_tender_1000a_jump_starter_power_pack.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74003c2c-2c78-44fa-b22f-426cb7804ea3/how_to_see_log_table_in_hindi.pdfIn PDF document text
    • https://85fc0914-20e3-4f1c-be8c-de7e6f89f47e.filesusr.com/ugd/a44510_f68547e9446047758d5c596d3d247237.pdf?index=trueIn PDF document text
    • http://wilaroxu.atwebpages.com/cetoacidosis_diabetica_criterios.pdfIn PDF document text
    • https://s3.amazonaws.com/zafijukopa/free_coloring_sheets_of_butterflies.pdfIn PDF document text
    • http://gipebevu.atwebpages.com/93814196252.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2337a407-9151-495d-b56a-ebb644271545/when_are_beats_pro_colors_coming_out.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_off0000d7ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7FF 5460 bytes
SHA-256: 426dde3aedcc8cda8d8c3b6e9c0a2790152d7688035ec36bc85fd20fe57500c4
font_01_sfnt_off0000eaa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA4 11524 bytes
SHA-256: c17982a8b57a11e9078a4a113f8517cafabbb781ffaab9efba17a5d44e847acc