Malicious PDF — malware analysis report

Static analysis result for SHA-256 518ff1c6a78244cd…

MALICIOUS

PDF

71.4 KB Created: 2021-06-18 15:14:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: d4ccbf0fa7a422952d5996b25746fba3 SHA-1: 604f0284ff0ec54c0da0d37673b6fd18552a9299 SHA-256: 518ff1c6a78244cdf66101552bf02ea6ff52c31a1fea3719ad4b7ca7e040cd51
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The file's structure and numerous external URIs are consistent with a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ketchas.ru/uplcv?utm_term=formulario+de+integrales+pdf PDF link annotation
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608772dd18fcf---11205811401.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074627439934---27411788888.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d15c6e3bae---98656047734.pdfIn PDF document text
    • http://akifkasaboglu.com/esatfisek/images_upload/files/reguzoladoduw.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a09e1c02c2---jasegefazaw.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160c3634b9ab76---jisinoliwaxerojelup.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/649693423f4910d4f551a744de7921ba/19791392806.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/c0c69a768be53255daa33c202319e4ce/fapikosaka.pdfIn PDF document text
    • https://prosperitas.be/data/assets/file/jubow.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/tga1jao7u0qav6rhn90e0rp6pt/53713281198.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5f540e56c---93279652294.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/df7a322bcb2c20b725c8948cf11dfddb/kotovivojuvowopovuwij.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/33035479694.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • 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_off0000c378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC378 5316 bytes
SHA-256: 10de927c54c7fa748b6c967805f95cf4ac661deae0778505eeaab557285fce63
font_01_sfnt_off0000d577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD577 11380 bytes
SHA-256: 4bbc604f0023b6ba824d4366853c1b307b9f9ff1a0f41280915f9fd63d284519
font_02_sfnt_off0000fb81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB81 16144 bytes
SHA-256: fb10e5badbbf29d6a05184c763452604a6d256f7c208a2bb674868c670b14a78