Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9b479a58f832526…

MALICIOUS

PDF

79.4 KB Created: 2021-06-14 18:34:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 70fd5ab5c05b9d443919fe94c1b43c86 SHA-1: 5657e4e2eb4d378231913e2232e4b9eff27c7e7b SHA-256: e9b479a58f832526673b3d85eaa400a7ef9dead8ceab41716ec233e9aec2bab9
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting it functions as a link farm for phishing or malware distribution. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of external URI heuristics points to the primary attack vector being redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://ketchas.ru/uplcv?utm_term=david+mcclelland+theory+of+motivation PDF link annotation
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab49d67a4bb---11374067868.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160bcad2f692c1---begufumivodiluroki.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/badezabolosidetosa.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ac541ebbd76---junowetunogolelupitumij.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/66103992764.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16081e4eb11e13---jiravagufiwavezabujeb.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/fowebolo.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160b9452daba07---24891056572.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b9f20b0a2---41381401430.pdfIn PDF document text
    • http://fernandopelosini.it/userfiles/files/zuniv.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160893d235bb55---2353454779.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16086658d940e5---vewobenuzumulu.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607db3ec7053b---jigujojazojufages.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6c5ac4898---9216297814.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/kexupebapadikuzu.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/33m43jk8n341m773883niq97hk/duzek.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8A 5244 bytes
SHA-256: d46b1b69f5683d9de2740987eec9efaec884c1b813186f3295cc73f7db988612
font_01_sfnt_off00010c4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C4A 10620 bytes
SHA-256: c1632c619e4efc9d1ad643f53a1d57ec2c7a3b76c71f1d366b60f6b63c0bfd0f