Malicious PDF — malware analysis report

Static analysis result for SHA-256 5de401b966698037…

MALICIOUS

PDF

89.9 KB Created: 2021-09-06 03:57:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 715f309eb30b53f36007f31e105b2ff5 SHA-1: 4675a161861e05b5eef61399f947f44fac8e8579 SHA-256: 5de401b9666980375e9bb98b48521f2e96b7278267c7a3a938d3ab941732214d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it is a link farm pointing to numerous disposable domains and compromised CMS uploads, suggesting a phishing or malware distribution scheme. The PDF structure and embedded URLs are indicative of a spearphishing attachment, likely leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://ellissi.org/userfiles/files/dexiwufugijapulesisub.pdf In PDF document text
    • https://fond.ru/userfiles/file/zipatogilupigifejub.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/b373473su7e0a7k9b2a8pq0ih3/genejumev.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/joxuxibusumo.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/66915428b41a8ed03f5ab8c1991bd1cf/39151054445.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091fbfa5e7eb---kigavexifatijapes.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/42115968894.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/saxiseropedovoxegi.pdfIn PDF document text
    • https://rijst.nu/userfiles/file/fidusififomaxaguwapixugo.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/63490637609.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/13970013067.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/defuvaxafigopogavotiroruz.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/c9v8h59g3d48g4dbbktg9mpkql/38394772580.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/6358ccea8b82939aa5a2a5983205e703/bodetegemewujakinomiwoxel.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160ac183710c31---31831511431.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/benarabos.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/lraomj55lgmr5k41sdji5h0mib/47744896580.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/ec091bdd904e209aabeb2ed0ebc96963/nikemuzu.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/kupadodabojojilez.pdfIn PDF document text
    • https://cargobull.cz/res/file/kavako.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/82689185726.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/d82e219e1dfefada1120d1cd94d86693/xoxiwabififanofobajebulep.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/lasijajowuvojekuzupa.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc58681e1ae---87449520960.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc7864c1d0---moxinefukekuvanufaruvoj.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/vuxepo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=call+of+cthulhu+d%26d+pdfPDF 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_off0000fae6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000112f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112F8 18708 bytes
SHA-256: c4548d44567e6d6126d99754fb02908c1d08931a62dbcf0fb7abaf3feec6b4b7
font_02_sfnt_off0001431e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1431E 10108 bytes
SHA-256: 36b5c18a9b48174080a1cca263ae9eacbcac75834ccdb33e54c87c55ceee7827