Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b73402b8667f449…

MALICIOUS

PDF

75.4 KB Created: 2021-04-09 01:43:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 2369f0638707377103fe6ff5ac64a0b5 SHA-1: beee0ead37344847876056be8845f9ca0c210e33 SHA-256: 3b73402b8667f449a4f8707432538e0eb19356b086ff0444a8d0edea269671c4
156 Risk Score

Malware Insights

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

This PDF contains a large number of external links, many of which are to benign-looking documents, but one suspicious URL (https://nipisod.ru/strik?utm_term=d%2526d+5e+homebrew+class+guide) is present. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the PDF structure itself is used to host and present these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 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.
  • 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://nipisod.ru/strik?utm_term=d%2526d+5e+homebrew+class+guide PDF link annotation
    • https://cdn.sqhk.co/sitopizol/ez2gcij/fastest_bowling_record.pdfIn PDF document text
    • http://generalmassage.online/canon_ip2770_print_head_alignment_problemgk93a.pdfIn PDF document text
    • http://zoneeuro.pro/wukuxirnejwn.pdfIn PDF document text
    • http://disclosures.space/cfa_level_1_feb_2021_exam_patternzemxl.pdfIn PDF document text
    • http://garantiya62.ru/relukedopuvinotogodunuxab7k17d.pdfIn PDF document text
    • https://cdn.sqhk.co/bareziwo/jehcbje/free_gems_dragon_city_app.pdfIn PDF document text
    • http://coins24h.com/lotuveletvh2sw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://332892e0-6a2b-40ad-946e-e7c92c61c867.filesusr.com/ugd/3e5d97_50fe6346009f43eb9df5b4454b1233e5.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wewiro/eular_vasculitis_guidelines_2016.pdfIn PDF document text
    • https://288c7b4b-0494-48f6-8ee2-9dd519b96b0a.filesusr.com/ugd/a107db_393f345eefa2454aa936bbdfaa290daf.pdf?index=trueIn PDF document text
    • https://0a497e50-07dd-462d-832d-d8678f741a8e.filesusr.com/ugd/5f857b_1ee641500cbf43c3aed374a6ed1d6538.pdf?index=trueIn PDF document text
    • https://2a082fd4-e93f-4b8e-9e59-408fa046b31c.filesusr.com/ugd/e334dd_a2d041ad9d6a43e686b0060881ff33fe.pdf?index=trueIn PDF document text
    • https://95fbbc11-640f-4658-acdf-6e09da746871.filesusr.com/ugd/e42ee3_e75a23f7ee1646ba9fc2b7763527f4cd.pdf?index=trueIn PDF document text
    • https://4c72699b-aa2e-4dc8-8bd5-1a54e8f938a6.filesusr.com/ugd/f3cb45_037ec3dc1bf24c8a8c8047648874b881.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xukirizugukugi/ui_designer_portfolio_templates.pdfIn PDF document text
    • https://dda5c79a-a75d-44d9-a006-48dec3bfe172.filesusr.com/ugd/115d6e_2cc8d4f1052c421c93d4dbc37a736eb2.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/baritexovopa/wejejemevi.pdfIn PDF document text
    • https://80b2a579-f9ed-4aa0-b91a-ac3c8973c086.filesusr.com/ugd/353d00_11a2a777cc054422822bfd2ce1934027.pdf?index=trueIn PDF document text
    • https://804b95bc-9ca4-448d-a094-5a8e1ff69a26.filesusr.com/ugd/99d1da_a149c085cd344c4badb55cddfe315bdc.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/firudegix/bpsc_2018_prelims_question_paper_with_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/baposivarabuj/what_do_the_cards_symbols_mean.pdfIn PDF document text
    • https://s3.amazonaws.com/tikofaketonub/best_nlp_books_on_audible.pdfIn PDF document text
    • https://s3.amazonaws.com/zarevizebi/archero_guide_best_weapon.pdfIn PDF document text
    • https://s3.amazonaws.com/rikolesafuwofar/how_rich_is_rich.pdfIn PDF document text
    • https://s3.amazonaws.com/ruzumeb/computer_accessories_with_price_list.pdfIn PDF document text
    • https://4bf641bf-117a-4913-931f-55e49063997f.filesusr.com/ugd/5befcb_c40c632b92934ac69123bddecfb31af4.pdf?index=trueIn 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_off0000ee6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6B 4156 bytes
SHA-256: 5bcf7f318894cd8667f709bf970fa8c582a8027402ea75fdf14ac0e15260a4d2
font_01_sfnt_off0000fc99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC99 10612 bytes
SHA-256: 37a40e31c785a8448ef75ea6983cfe7b78f21ffccb34e22ff262c75e61099e44