Malicious PDF — malware analysis report

Static analysis result for SHA-256 71efe349c234de37…

MALICIOUS

PDF

89.7 KB Created: 2021-03-14 12:38:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: aeace0b133f9c0ae7c80832dbe019771 SHA-1: 1b6c2c9fdecd386bc1e1cbb88b3f955eaaa51364 SHA-256: 71efe349c234de370c9290f461b4032b2d02e0afa9a6af4a49421f6bc1b7f70f
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged by ML classifiers and ClamAV as malicious. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using many links on disposable hosting, suggesting an attempt to obscure the true malicious destination. The primary malicious URL identified is https://crophysi.ru/wix?keyword=physical+science+mcq+question+and+answer, which likely serves as a phishing or malware distribution point.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crophysi.ru/wix?keyword=physical+science+mcq+question+and+answer PDF link annotation
    • http://mevukavotidu.getenjoyment.net/mainstay_computer_desk_instructions.pdfIn PDF document text
    • http://xolokukifimiv.sportsontheweb.net/denisufimiludikegoz.pdfIn PDF document text
    • https://pesudimudoselu.weebly.com/uploads/1/3/2/6/132681392/famulibazijazep.pdfIn PDF document text
    • http://rolapisi.scienceontheweb.net/23250604172.pdfIn PDF document text
    • http://avit0.pro/denon_avr-2113_netzwerk_hdmi_av_receiverouddw.pdfIn PDF document text
    • https://wuxelulomevadi.weebly.com/uploads/1/3/4/9/134904547/komisob_rigipixeja_widapurajumoli.pdfIn PDF document text
    • http://podipotekoi.ru/download_tafsir_al_misbah_juz_30ggqwy.pdfIn PDF document text
    • https://xotozefubineru.weebly.com/uploads/1/3/4/5/134576546/9887079.pdfIn PDF document text
    • http://compte-cmbretagne.best/zetiwarp4n7a.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/506b15bf-9f6d-4a8f-af60-12140641c877/litejawemifukuwijaraxabu.pdfIn PDF document text
    • http://vizomonuzujo.onlinewebshop.net/atrocity_act_1989_in_marathi.pdfIn PDF document text
    • http://zovagupegi.rf.gd/75931344107.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/678db15c-2f17-4061-90dd-949dab83e654/33520232156.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/616a2277-7f7e-4944-930a-63ca7d35a63f/2012_chevy_impala_lt_for_sale_near_me.pdfIn PDF document text
    • http://fisuzes.epizy.com/quantos_numeros_tem_no_titulo_de_eleitor.pdfIn PDF document text
    • http://faxiruvud.myartsonline.com/elven_pantheon_dnd_forgotten_realms.pdfIn PDF document text
    • http://xupewosupegosax.epizy.com/please_answer_my_question_peter.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_off00011fab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FAB 5500 bytes
SHA-256: 71705db933cf4b74153fe044568d2d3a1edbaee8b0ca609c713221a1590b0599
font_01_sfnt_off00013248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13248 11640 bytes
SHA-256: 726e8fa3a99827845191330abf033486b254915118faf93c384ae21cff6fa763