Malicious PDF — malware analysis report

Static analysis result for SHA-256 43cf7f42267fb02b…

MALICIOUS

PDF

84.1 KB Created: 2021-05-14 07:18:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 5d015d0d2e1016e364ccdbfe598b6aef SHA-1: 65ed937a32b5a03c5880ea38a2a634f6ed587d9d SHA-256: 43cf7f42267fb02b4de40bcc3e6c6c1a16bf5f1deaa924ccf5ef5925cb768ef8
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many pointing to disposable hosting services, suggesting a link farm or phishing attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high volume of links on potentially untrusted domains. While no scripts were explicitly extracted, the presence of external URIs and the overall detection profile strongly suggest a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://jacksth.ru/strik?utm_term=questions+to+ask+interviewee+during+phone+interview PDF link annotation
    • https://cdn.sqhk.co/livulopo/hhgK305/pentagon_city_mall_stores_map.pdfIn PDF document text
    • https://nabisafuv.weebly.com/uploads/1/3/1/4/131413222/1440722.pdfIn PDF document text
    • http://nonowun.mywebcommunity.org/pavalelajenon.pdfIn PDF document text
    • https://lerasakob.weebly.com/uploads/1/3/2/6/132682990/zazulitebaxenir.pdfIn PDF document text
    • https://cdn.sqhk.co/nomevagume/EFSvOij/battle_simulator_prison_police.pdfIn PDF document text
    • http://wosozage.mypressonline.com/bukezovotitekodegol.pdfIn PDF document text
    • https://cdn.sqhk.co/xipepovivik/y7geHVT/zemulewalixafenosos.pdfIn PDF document text
    • https://sopaxibifezubin.weebly.com/uploads/1/3/4/6/134608036/9808218.pdfIn PDF document text
    • https://cdn.sqhk.co/vavewiminiv/dgd2Bha/labyrinthitis_vs_vestibular_neuritis.pdfIn PDF document text
    • https://tetarexaxamos.weebly.com/uploads/1/3/1/4/131483090/muxorajasamexudemek.pdfIn PDF document text
    • http://mosuxemapawezi.iblogger.org/60635864916.pdfIn PDF document text
    • https://suvuzijovibalis.weebly.com/uploads/1/3/4/6/134660606/8042fab207c.pdfIn PDF document text
    • http://rawoferifexa.22web.org/composition_of_functions_worksheet_1_answer_key.pdfIn PDF document text
    • https://cdn.sqhk.co/sixatowitur/A2Dejiq/xowig.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wesakuboviku.epizy.com/rerewipiwuniroga.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/46363415-8290-4dba-beba-eff7551800f8/how_to_find_cylindrical_volume.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/402a9e27-777b-4982-9051-a13fda320091/nfpa_1410_drill_9.pdfIn PDF document text
    • http://jabodegodonirad.atwebpages.com/febazetafo.pdfIn PDF document text
    • https://s3.amazonaws.com/mekonulegipero/fisifuvilivinikunaboradan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/195604ae-b174-4afe-a13e-2c3cb39e6b06/vigevaromisamifunadumazuv.pdfIn PDF document text
    • https://s3.amazonaws.com/mefadedosuw/angles_worksheet_grade_4.pdfIn PDF document text
    • http://fubageraj.rf.gd/breville_juice_fountain_elite_cold_press_juicer.pdfIn PDF document text
    • http://rawigukegopafot.onlinewebshop.net/zivudex.pdfIn PDF document text
    • http://nisinukodepafix.rf.gd/27976228023.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2a9e8d50-cafa-48c4-a04d-2f4c1b047a6a/58750455049.pdfIn PDF document text
    • https://s3.amazonaws.com/fosalizuzu/741784812.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/10c7a741-0cc9-40d7-97bb-57604d4a72ee/bikujuvasuzuzusojuj.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_off000109a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A5 5468 bytes
SHA-256: 48f685b7b0d22e1e453a04d7693a952e51cc36f581d716fba9889952e80f926f
font_01_sfnt_off00011c52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C52 11056 bytes
SHA-256: b5c4f5a2d44a754a5fe88731085119ae8d95261579668954c9bb21d8a82cbb6f