Malicious PDF — malware analysis report

Static analysis result for SHA-256 86a8206684e73f7a…

MALICIOUS

PDF

78.9 KB Created: 2021-04-02 23:07:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 6cb9777aa76fa218190833716f311248 SHA-1: d37fbffb66a745aa38aa8695e3a0e1563ee90b09 SHA-256: 86a8206684e73f7ad68e41c9c43a028586e286b561019ab26e326185bbf589df
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with several pointing to suspicious domains like 'midufefew.ru' and 'cdn.sqhk.co'. Heuristics indicate it functions as a link farm on disposable hosting, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the PDF structure and embedded links strongly suggest an attempt to redirect users to malicious content, aligning with spearphishing tactics.

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/award?keyword=essential+amino+acids+structures+pdf PDF link annotation
    • https://cdn.sqhk.co/fidapulano/ihaGhfO/mens_fade_haircuts_short_on_top.pdfIn PDF document text
    • http://gesajobode.22web.org/28286587556.pdfIn PDF document text
    • https://cdn.sqhk.co/puwukuwos/hhhiCjf/tulizon.pdfIn PDF document text
    • http://mavpa.fun/calendar_template_2019_printablewb4nf.pdfIn PDF document text
    • http://bojidodug.iblogger.org/satitodetamaberuw.pdfIn PDF document text
    • http://help-nanny.site/tuwaxefimokomepekavupb7b7m.pdfIn PDF document text
    • https://cdn.sqhk.co/linewebozid/ZXjajia/lasedexaxot.pdfIn PDF document text
    • https://cdn.sqhk.co/nuzinirumawe/jgnjjAA/idle_flower_tycoon_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/zifeduwa/AjjieuL/voltage_drop_calculator_meps.pdfIn PDF document text
    • http://domen3.club/xukatupejeg64nyw.pdfIn PDF document text
    • http://nemesun.iblogger.org/17477535783.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/33ead700-21f8-4358-9e75-0f7da9fb9258/mcculloch_string_trimmer_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0964cf5-4b64-49a4-b298-c85b029e6a30/mukojoratogijusi.pdfIn PDF document text
    • https://s3.amazonaws.com/tinezedu/zen_meditation_techniques_for_beginners.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09c29bb6-e6fa-4b8f-a46b-32235d06a451/11001810292.pdfIn PDF document text
    • http://rabijeno.epizy.com/ranemovavuzezubutuso.pdfIn PDF document text
    • https://s3.amazonaws.com/viregujipowuru/independent_sales_consultant_agreement_template.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e95effd-0351-479c-9dcb-dd4cad2c6445/21400675217.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/657ab9c6-79b1-4134-a83b-27140fefd00c/best_ipad_mini_4_case_with_keyboard.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5041b2e-934d-49ea-a775-035461faef99/94700281533.pdfIn PDF document text
    • https://s3.amazonaws.com/mesixadelomomo/mysql_client_free_download_for_linux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/23f20960-9717-4228-9b1a-6d40a778ba70/15775108548.pdfIn PDF document text
    • http://tafupudininidag.rf.gd/miferavinuxad.pdfIn PDF document text
    • https://s3.amazonaws.com/boduxatavepe/jejigegaxuf.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_off0000f994.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF994 5256 bytes
SHA-256: b8232879d56d21f6e3c24cb1d898792da9a10dfbbbe448a0aac649d38c8d20a8
font_01_sfnt_off00010b5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5D 10108 bytes
SHA-256: d62bf58f40649e7162a1372ec79b4ef8845410d66ddd9e2a70b01366883f167f