Malicious PDF — malware analysis report

Static analysis result for SHA-256 f59de84c4620b4ec…

MALICIOUS

PDF

71.1 KB Created: 2021-09-27 14:47:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8eafbfe6ec74baba0e86dff2c96e8668 SHA-1: 8b6229e5432338759a4a32fb5b8b28334c438074 SHA-256: f59de84c4620b4ecebde9d3935f5ce2349aefffdab01e125daaf88d67fd7b3ba
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and compromised CMS links points to a tactic of distributing malicious content through seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://laborke.ru/uplcv?utm_term=free+robux+without+password PDF link annotation
    • http://vdi.vn/userfiles/file/8072012717.pdfIn PDF document text
    • http://consultingexpert.eu/fckeditor/userfiles/file/nosodifajigediwaz.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615180e1df928---jizipu.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/86950422599.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/84069594041.pdfIn PDF document text
    • http://daiichigroup.net/uploads/news_file/wikawigeveduvikawire.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/9b545c75516c02b93c56386e5cdda27c/19637856548.pdfIn PDF document text
    • https://matao.ro/app/webroot/files/userfiles/files/madanajunavazuxadinipag.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/watiwevotof.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b74d9da77---bevakitenidelodirotegobu.pdfIn PDF document text
    • http://mutamobilya.com/images_upload/files/bolejejizetobod.pdfIn PDF document text
    • http://ciba.lv/uploaded/file/24687515163.pdfIn PDF document text
    • http://hamdannepal.com/userfiles/file/kavotojazepuje.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/57309032898.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c4a8b8fa8---66940132497.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/67499461778.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359581e2afa---titivijej.pdfIn PDF document text
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/dodexefezava.pdfIn PDF document text
    • https://www.rapn.ru/ckfinder/userfiles/files/32136324023.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/63587929141.pdfIn PDF document text
    • http://pbhdom.eu/userfiles/file/46750375282.pdfIn PDF document text
    • http://studiotecnicomancini.eu/userfiles/files/99286216600.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/55353067159.pdfIn PDF document text
    • http://eperon-kochersberg.com/img_db/69292464356.pdfIn PDF document text
    • http://modra-skola.cz/userfiles/file/tixifotarejiwi.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_off0000b4f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4F2 16196 bytes
SHA-256: 584f78d9874e971ca7e78943b0476d421954ec3159fa5a0793593484889ab02a
font_01_sfnt_off0000ddef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF606 10744 bytes
SHA-256: 088b1608646a465cf961a11349ec6c2981b838d59e9515b0a0de17d2c36a8158