Malicious PDF — malware analysis report

Static analysis result for SHA-256 d41dc01e319ceed3…

MALICIOUS

PDF

81.5 KB Created: 2021-09-24 07:13:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 522cb2155ee3d7d6a70afa627b780372 SHA-1: 35968029b6e5a3620754786398869fa9f64af17b SHA-256: d41dc01e319ceed30304557f81a8fcc9c7c7972db9ece0a47e4f14c31606210e
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs pointing to PDFs hosted on various domains, many of which appear to be disposable. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a high likelihood of this document being part of a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.mnogotrop.com/ckfinder/userfiles/files/37505716097.pdf In PDF document text
    • https://sambelteri.com/contents/files/gokewuzodiwonekal.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/ruxenaduxivanok.pdfIn PDF document text
    • http://nuocmambason.com/upload/fckimagesfile/458641f39cc333d06c2b9c524181b9a3.pdfIn PDF document text
    • http://pitin-akutsu.com/js/upload/files/10682561499.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/68949127814.pdfIn PDF document text
    • http://omni-links-europe.com/images/blog/file/76524888079.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/ranuloporega.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16144a5026934e---19614257454.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/bowubu.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/sejew.pdfIn PDF document text
    • http://eksternest.be/images/file/lomelaxirafereko.pdfIn PDF document text
    • http://nepalbestcargo.com/userfiles/file/47797149578.pdfIn PDF document text
    • http://ventiliatoriai.lt/js/ckfinder/userfiles/files/viwerepokuxinimu.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/3846705015.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/pidasupewasamuxidew.pdfIn PDF document text
    • https://lyonsinn.com/nbloom/fckuploads/file/tufifuxobimawaf.pdfIn PDF document text
    • https://dcimx.com/files/tamubunixipenoguf.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021092406464445.pdfIn PDF document text
    • http://zlzljc.com/uploadfile/file///2021090722313430.pdfIn PDF document text
    • https://directorvincentchow.com/fck_filemanager_upload/file/73217744431.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/080bb1c0cf663dfb9ec4a635d3a53124/94260644676.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/59166327229.pdfIn PDF document text
    • http://119pump.net/d/files/vixukeranezoxodop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=rope+vice+town+mod+apkPDF link annotation
    • 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_off0000d964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD964 17912 bytes
SHA-256: 8ad2e05e43761538bf206bed8cb5fd320a21cb904bdc5e5e74a5070a543e9a88
font_01_sfnt_off000107ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12001 10652 bytes
SHA-256: 1c7b37e5a9ac3ceb5e3748b27e19bf799daa7b55b8c3f07c7e14e6f3fe8109b3