Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dc23d3b0bd13be8…

MALICIOUS

PDF

74.1 KB Created: 2021-06-10 09:47:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 59acea49d8de889f3079836f97ad8694 SHA-1: e2b53fe84473edf1723133571930da78dcd7c555 SHA-256: 9dc23d3b0bd13be86247bed94064498df120e037d7e84646d1b252c1aa320161
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, and contains numerous embedded URLs. One of the primary URLs, 'https://midufefew.ru/123?utm_term=new+guidelines+ldl+cholesterol', is hosted on disposable infrastructure and appears to be part of a link farm, suggesting a phishing or malware distribution attempt. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL usage point to a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://midufefew.ru/123?utm_term=new+guidelines+ldl+cholesterol PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4407807/normal_60319bdab52c8.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4369494/normal_60b195a2955e3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4478655/normal_5ff653f15d3a9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459780/normal_603c32912ffb9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369191/normal_60c04fd4c1aaa.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/146f35d9-04df-49e3-9929-356eb8a44628/peter_pan_play_script_jm_barrie.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6756a6a4-837e-4e1e-83ac-ecbe6eb443ea/8025686941.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e7419c8-0bde-4e70-b086-9d26561a99a7/datamutivozozafojinivo.pdfIn PDF document text
    • http://favixose.pbworks.com/f/18039386271.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ca88210-acac-40e5-94e4-7d516a2f6a9f/68863639166.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e24ba44f-fb0c-4717-9504-e8a02ef9e7ab/71314710605.pdfIn PDF document text
    • http://fisakujimet.pbworks.com/w/file/fetch/144830529/54593351844.pdfIn PDF document text
    • http://xobapotowi.pbworks.com/f/pofemisosofetuf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/635cfee1-6db1-41df-b1e2-7a0d6a297e7b/pamadif.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af4cb8b4-bbe1-44d7-95b4-6359e5e4590e/sikoxixetotitumemakematel.pdfIn PDF document text
    • http://mogulazedub.pbworks.com/w/file/fetch/144523695/how_to_edit_a_bank_statement.pdfIn PDF document text
    • http://dojejezo.pbworks.com/w/file/fetch/144797877/wings_of_fire_book_3_the_hidden_kingdom_read_online_free.pdfIn PDF document text
    • http://sijomirurefi.pbworks.com/w/file/fetch/144453069/daily_attendance_register_format_for_employees_in_excel_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/079147d9-714a-4a12-a6d0-ea819ad9c570/vozirefokudapivexegef.pdfIn PDF document text
    • http://doxawadar.pbworks.com/f/sixaxis_controller_no_root.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4c89b56-ffeb-4f5f-be7f-f997f4ae319e/jugipu.pdfIn PDF document text
    • http://jowugaredite.pbworks.com/w/file/fetch/144972696/4781708916.pdfIn PDF document text
    • http://sujagajo.pbworks.com/w/file/fetch/144843324/red_lobster_hours_on_easter.pdfIn PDF document text
    • http://ruwomodanom.pbworks.com/w/file/fetch/144475554/physics_textbook_for_secondary_school_in_nigeria.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c585672-fcb4-4476-b3de-242481a73a56/lopagasojojomiwofi.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_off0000e4a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A7 5052 bytes
SHA-256: 7ad2fabb9fc48150529a006d9c1860473f13484abf391152ba9570e0661dcf26
font_01_sfnt_off0000f5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F0 10868 bytes
SHA-256: 277605c37968968aad2159a998e6374d6adc57baff8bf18e85ea4a8b1360a4e0