Malicious PDF — malware analysis report

Static analysis result for SHA-256 7dcfb8a7cb4026e1…

MALICIOUS

PDF

70.9 KB Created: 2021-10-03 14:54:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 018bdb1b237d16aa82b6e3dde966cc09 SHA-1: 5985f83007fa3572df0fa0d6c4a0d9feb77d9097 SHA-256: 7dcfb8a7cb4026e1b450e10cec48e890f09aaab0e0f2f84e97fd371685ff73c6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are hosted on disposable domains and utilize UTM parameters, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to malicious websites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://nomylo.ru/uplcv?utm_term=go+along+with+crossword+clue PDF link annotation
    • https://khoahoc.timviec365.com/picturesfiles/xatixagosogifubemi.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/16279858720.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161494c766b542---58692760810.pdfIn PDF document text
    • http://bright-inter.com/file_media/file_image/file/jeximodikuvu.pdfIn PDF document text
    • https://euinsuti.uniluxgym.ro/app/webroot/files/userfiles/files/delakidasesaf.pdfIn PDF document text
    • http://opt-russtd.ru/data_center/upload_pictures/file/bexoboj.pdfIn PDF document text
    • https://phukienbep.net/media/files/finedi.pdfIn PDF document text
    • http://lienming-rubber.com/uploads/files/202109251900121218.pdfIn PDF document text
    • https://saptabangunmanunggal.com/indomobils/upload/file/zigolisuzolixataf.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/gozunifebomagipokasogov.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109160525079560.pdfIn PDF document text
    • http://rhondadejean.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/77844816902.pdfIn PDF document text
    • http://svx.su/ffile/file/48974740577.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/jatitarifibeka.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/guvuvogabenenojepamegal.pdfIn PDF document text
    • https://www.ftha.org/admin/ckfinder/userfiles/files/teraz.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/92c557a8a2307448b79db1304d3f6b21/13639002963.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109281756322267.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/bamolinuzomerolozaxesun.pdfIn PDF document text
    • https://floresdeserrezuela.com/aym_image/files/35891906338.pdfIn PDF document text
    • http://ageddfjtj.pretty-match.com/upload/files/23016648755.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/8671269385.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/bofopedu.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/kurowafowobepekorilisazes.pdfIn PDF document text
    • https://vinatech.com/userfiles/file/lasuxiz.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/46241496588.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB520 10876 bytes
SHA-256: bd7705103d678e6ec563a605093425dea5a905e616a4859a2ccec8b9bbee3b8d
font_01_sfnt_off0000ce19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE19 15352 bytes
SHA-256: 17be97d67753aec988ac391888f9c10371b6c9e08e9bfccbabbbbdc46630fd5d
font_02_sfnt_off0000f542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF542 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1