Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b71bd2db977f098…

MALICIOUS

PDF

83.8 KB Created: 2021-09-14 02:32:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cec669eb7854d1c3ae381402de0c70fb SHA-1: 98ecdde06164e4d6b2b9c44135bf42e59ad42683 SHA-256: 8b71bd2db977f098b0ba8e5edbde0fdb010ffdaedc8baff8ae4592518c21ac54
126 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=zygon+doctor+who PDF link annotation
    • https://alpinismbihor.ro/app/webroot/files/userfiles/files/20800671756.pdfIn PDF document text
    • https://csodamalom.hu/files/files/59989443710.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/musisewixuwoniraxarosus.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109131838408751.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/komijazujusosibomev.pdfIn PDF document text
    • http://chinamakina.com/userfiles/file/97878652676.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/5221ed7ddebb93fc47802257d90534c9/8854201085.pdfIn PDF document text
    • http://hamyarsanatco.com/ckfinder/userfiles/files/8793220888.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/4459323804.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/mipugokutevudipitinug.pdfIn PDF document text
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/sivomifuvadilikuwib.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/fatetunogire.pdfIn PDF document text
    • http://combatkuntao.com/ckeditor/ckfinder/userfiles/files/75646908555.pdfIn PDF document text
    • http://bolt-go77.com/fckeditor/userfiles/file/20289608112.pdfIn PDF document text
    • http://alfadent-volg.ru/images_uploads/files/texegovumofa.pdfIn PDF document text
    • http://strandedtattoo.net/file/kusapediligaxi.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/vebowobomipubaramakomides.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/fivobosorivi.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/6630116755.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/supupozunabiwosuluranak.pdfIn PDF document text
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/28350549764.pdfIn PDF document text
    • https://heritran.vn/uploads/news_file/xepete.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613fde8f52ed9---walazu.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/nuperujagube.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_off0000e316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE316 10212 bytes
SHA-256: b2fa58fd8be25beccdc96a6038a94a9bf08d4dc87484a56778460b79dceec2d9
font_01_sfnt_off0000f9bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BC 18408 bytes
SHA-256: b13598919b550b9d771b6570ee4e18da897272dc0cfe359222e090732eeb4f88
font_02_sfnt_off00012a39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1