Malicious PDF — malware analysis report

Static analysis result for SHA-256 b03c32fdd2d859ed…

MALICIOUS

PDF

67.8 KB Created: 2021-06-11 15:29:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 40e6bd577cac235c58ea819ef036b748 SHA-1: 777e8cad591cdc2679ddac0f458742b568f7537c SHA-256: b03c32fdd2d859ed5e7d0e46a9f1aa43e836d2c39178babd91b6235ee636c745
156 Risk Score

Malware Insights

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

The PDF file is identified as malicious by ML classifiers and ClamAV, and contains numerous links pointing to compromised WordPress sites. These links are presented in a link farm structure, suggesting an attempt to redirect users to malicious content under the guise of academic notes. The presence of external URIs and link farms on compromised CMS uploads indicates a phishing or malware distribution attempt.

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://synerhu.ru/uplcv?utm_term=campbell+biology+course+notes PDF link annotation
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16083b122daad5---13742699785.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084bcfdcead6---bovoleva.pdfIn PDF document text
    • https://www.colours-of.com/wp-content/plugins/super-forms/uploads/php/files/5plcjdhqjs9ngm78jptib8e699/tikojiduzuribigobiz.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/6805021526.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a32fc3aef3---59190210538.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a92c35e903b---7689372858.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/91504925501.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/32ce5e11004a06ffa2bdc5389211bdfb/robusivibadudofutijowaxi.pdfIn PDF document text
    • https://munord.com/wp-content/plugins/super-forms/uploads/php/files/8e43797b7d2998a85b97b9058c25232f/56987633611.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3ef9752e247c9512d2365cb69b311f70/tibeturenewowuti.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/072b556f4c30306d59e16129d7caf3aa/20260036382.pdfIn PDF document text
    • http://elturo.ru/img/upload/files/xarizejalab.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/3loadtm42evdi4phqcv85t7t4o/93608747535.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082bc4673dc4---63777627073.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb4b29d355---40528434208.pdfIn PDF document text
    • http://poorclarescork.ie/images/57268772355.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/068lercongcr6js2qt6gef9292/lojuno.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_off0000cc17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC17 5400 bytes
SHA-256: c9862c3a7e19ecbc277098a87e521ae0d2d2924348748adafe471e61ab5c1b7b
font_01_sfnt_off0000de61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE61 10468 bytes
SHA-256: 8a5cd3e0c7590e661c6e9ed45096502041df4602d06a8f062b65041f3ac84e85