Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd510da20d4eaac6…

MALICIOUS

PDF

80.5 KB Created: 2021-03-15 02:44:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 90d936359776471bf197955c1b370a7b SHA-1: da62075de0546c1fe0a429a82d7aedc43bf48623 SHA-256: cd510da20d4eaac6c473e9e5b073fcb97180067188b58d21fc416cad53c9dd3c
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs pointing to disposable domains, suggesting it functions as a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies it as a link farm on disposable hosting, and the presence of 'utm_term' parameters in some URLs further supports a phishing or malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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 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://gimoguvi.ru/strik?utm_term=skyrim+nintendo+switch+tips PDF link annotation
    • http://trysalon.xyz/how_to_prepare_used_cooking_oil_for_biodieselzen2v.pdfIn PDF document text
    • http://wixiziz.iblogger.org/tadalerabixisaduwefabono.pdfIn PDF document text
    • http://loleveze.iblogger.org/contador_publico_concepto.pdfIn PDF document text
    • http://mugedly.xyz/pdf_math_grade_10_answer_key66djn.pdfIn PDF document text
    • http://pumidafefisun.iblogger.org/78195935242.pdfIn PDF document text
    • http://ideal-it.fun/jodagaleruwo3174v.pdfIn PDF document text
    • http://panasawivop.iblogger.org/rilanexebus.pdfIn PDF document text
    • http://natlab.ru/sapo_y_sepo_son_inseparables5u75q.pdfIn PDF document text
    • http://afracheat8.xyz/big_ganga_bhojpuri_channel_appsvl5um.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/d525c8d7-6752-4b8f-ab28-d9251faad8a2/what_is_drama_in_literature.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81a93738-d035-46a3-a775-5c1c244d2be7/76262077482.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c88ea172-3be3-4d20-96fc-24027faae90c/16714396454.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/033139f4-287b-452d-bd1a-2b3cffb4c7d7/which_bts_member_is_the_kindest.pdfIn PDF document text
    • http://muxugozobizesex.epizy.com/the_best_2_way_radio_reviews.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9eada2ba-4109-465a-a759-750c25f6bacc/are_all_ly_words_adverbs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/028f9c05-a7ae-4bc3-80c9-0dd603231863/31635029334.pdfIn PDF document text
    • http://vaxomuterok.epizy.com/michelin_guide_france_food.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f75b089-1d75-4b23-8eee-4f5d4bcf6144/landice_l7_pro_sports.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18302ee0-6b0e-4c36-af9a-851d558eb628/post_office_mail_rates_for_international.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/12e1020e-65e4-44e4-a64a-890f27bfc30d/matlab_scatter_plot_color_gradient.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e853d26a-245e-4a72-b462-a70dffa00184/jotefilavajovoxipidawifa.pdfIn PDF document text
    • http://vujesidewu.rf.gd/joraxerib.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c40f0253-761b-4df8-9bc2-d386f3b47db6/mupojudabe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8269fe98-36e3-4dcd-9d39-278705e3d51a/what_is_ship_insurance_in_star_citizen.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_off0000fe16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE16 5432 bytes
SHA-256: 754231715dcb6b8bf02114c0e772ba8e2c65294ec30d550a3dba3b1fb19d208f
font_01_sfnt_off00011085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11085 10668 bytes
SHA-256: b00cd7abdc20b7aa67ccb16b98e2c60235cbaf9b9f2da2f8353762370036ec9e