Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f6ca42185a8ffb2…

MALICIOUS

PDF

79.1 KB Created: 2021-04-27 20:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 4cafa9c117f191db8311e29570737f4c SHA-1: a45854efd790b5b896911f5f9dd20cd384122c4b SHA-256: 3f6ca42185a8ffb2e275a9a9db39ba1767ced9e93d390fd600ac27fcf8906900
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous external links, including one to 'kuzutuzo.ru', suggesting an attempt to redirect users to potentially harmful sites. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports its malicious nature, indicating it's likely used for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://kuzutuzo.ru/strik?utm_term=o+que+devemos+comer+para+n%25C3%25A3o+engordar PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4382952/normal_5fc661ba092dc.pdfIn PDF document text
    • https://cdn.sqhk.co/tipekafomube/eOUFdge/top_90s_music_groups.pdfIn PDF document text
    • https://cdn.sqhk.co/lepapina/lJOjihf/vusiwuporiresaxuka.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424349/normal_60696c657f18b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385648/normal_60638e1a670bc.pdfIn PDF document text
    • https://cdn.sqhk.co/dijabidasu/c0Ygfjj/warship_fury_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/gobopovupav/ipwhcaX/god_simulator_roblox_codes_wiki.pdfIn PDF document text
    • https://cdn.sqhk.co/wezikinupig/axjeXEc/dc_volt_amp_meter_wiring_diagram.pdfIn PDF document text
    • https://cdn.sqhk.co/vameduvide/Qjiklq9/mineral_oil_laxative_walmart.pdfIn PDF document text
    • https://cdn.sqhk.co/pilozarager/geBiaha/draw_a_stickman_epic_3_all_pencils.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://a26b494c-4f54-4b9d-aaa3-e02d462d315a.filesusr.com/ugd/c6268f_9a53e34baaf84ba5ab1cc49d0fe424d2.pdf?index=trueIn PDF document text
    • https://9a86171b-24d8-4f43-8717-687e75280c8f.filesusr.com/ugd/6234e8_7f8f548f3802498281f491c4ca4da1dd.pdf?index=trueIn PDF document text
    • https://b01ec662-dec5-4f54-b977-8708717d6054.filesusr.com/ugd/07e02c_e78d87286af84da2810882c8dfc2ff53.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/561a8c4e-dd6a-4241-a7f6-47c595e1114c/how_to_transfer_video_from_canon_to_mac.pdfIn PDF document text
    • https://3a5aa097-47f9-475f-9992-83bceef25cc3.filesusr.com/ugd/f55bec_d219700d7aa6455bb2eae50ec25ee2bc.pdf?index=trueIn PDF document text
    • https://5ec50ee2-6c76-415b-b731-82d7de26534b.filesusr.com/ugd/826e74_8ffa876cf76e453d8e072f3d48136883.pdf?index=trueIn PDF document text
    • https://24d1f61b-f5c5-4d2f-8180-62589f44e8d8.filesusr.com/ugd/eed56f_f65b80258f524dffa7e0757562ea0c17.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/66fb539b-cc7a-4152-a3e3-24d7d1bd9d7d/89179446129.pdfIn PDF document text
    • https://7c3dd69e-6649-485e-b385-36acc2971cd6.filesusr.com/ugd/cf9ff1_36ebcbaa6aba4c5ca640d9bce94a909e.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_off0000f060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF060 5892 bytes
SHA-256: 3bc8a5817d5fb000749d9fa9697691efacbe77e37433aec5c9f8997f0dc26bdf
font_01_sfnt_off000103c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C5 13328 bytes
SHA-256: d8a5db6c36ec73091b324ee36c7f29f0584b19574d5f4f489f16adc928a4d75e