Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3d8ce51eb06ae2…

MALICIOUS

PDF

86.6 KB Created: 2021-03-16 21:47:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: cf28fba3e997728bc0141326095456ba SHA-1: 8eff777efe02c3d9f5a4043353a87acfbd408394 SHA-256: ac3d8ce51eb06ae2bd0f3771b2166f8aeb5abcbfb1bc6b3c63b640f65a54ed3e
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links pointing to external PDF files hosted on various domains, many of which are identified as disposable or malicious redirectors. This behavior is indicative of a link farm designed to distribute malicious content or phish for information. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/strik?utm_term=coleman+powermate+5000+service+manual In PDF document text
    • https://cdn.sqhk.co/dorusafe/2gibYYY/jafibikupuji.pdfIn PDF document text
    • http://zonerokemub.getenjoyment.net/how_to_get_a_vet_assistant_certificate.pdfIn PDF document text
    • http://naturaleone.space/letter_format_for_absence_from_workyoarm.pdfIn PDF document text
    • http://gekifek.scienceontheweb.net/gumetaxinabawidiz.pdfIn PDF document text
    • http://dapovevi.mywebcommunity.org/australia_rail_map.pdfIn PDF document text
    • https://cdn.sqhk.co/totafeta/itjeBjc/15586960270.pdfIn PDF document text
    • http://fatunatet.getenjoyment.net/alphabet_japonais_franais.pdfIn PDF document text
    • https://cdn.sqhk.co/xawobovuji/fRM0mTj/passcode_lock_screen_turn_off_time.pdfIn PDF document text
    • https://cdn.sqhk.co/pesasotiro/PggoGid/glitter_live_wallpaper_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/jopubelo/haiexif/explain_how_to_manage_a_business_budget.pdfIn PDF document text
    • https://cdn.sqhk.co/nixafusoda/iEQ3dha/best_jet_fighter_games_ios.pdfIn PDF document text
    • http://vaxiliwu.medianewsonline.com/math_games_place_value_blocks.pdfIn PDF document text
    • https://cdn.sqhk.co/rolileduvof/aKxHghq/the_solar_system_song_rap.pdfIn PDF document text
    • http://7gusevshop.website/39527998109e0djp.pdfIn PDF document text
    • http://topsol.xyz/data_analysis_with_python_projects_-_mean-variance-standard_deviation_calculatorz8ypx.pdfIn PDF document text
    • http://fijazubelanulek.mywebcommunity.org/26139493861.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b56e00ce-d729-42e9-814b-b9a4b194f5ba.filesusr.com/ugd/f6f93f_7ad70f48cb6e46c5926ec0ded717bd1d.pdf?index=trueIn PDF document text
    • http://xefiposokupama.myartsonline.com/afcat_question_paper_2020.pdfIn PDF document text
    • https://ce2645ba-e89a-43d5-afff-5c0150757291.filesusr.com/ugd/c63dba_745e3e22ae1644cc87d8691e7d5418ad.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_off00010869.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10869 5404 bytes
SHA-256: 71506dcdc042f80279b628f80c0ec4f8e1fcfd9ab9d7956505b5f510f31f0a01
font_01_sfnt_off00011abe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABE 16280 bytes
SHA-256: e3f7779f5889bdedc4d26f3c34fb6fa8e0cd58d2cd89e1a593d3f8b25e314f00