Malicious PDF — malware analysis report

Static analysis result for SHA-256 85b3a0d5440ac43f…

MALICIOUS

PDF

83.8 KB Created: 2021-06-20 03:15:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 120bdad3b7321f9c32ff8bce65fc2906 SHA-1: 6aeade44931a206474765373ad7d006310a37d2d SHA-256: 85b3a0d5440ac43feebb0d50ff23a4d5da2e4891da5d9649f08283cbc03f24f6
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. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload locations and potentially disposable hosting sites. While no scripts were explicitly extracted, the PDF structure and link farm behavior suggest it's designed to redirect users to malicious content, likely for phishing or malware delivery.

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 http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a67bc227bf0---vevovodevera.pdf In PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cad32274379---79141534103.pdfIn PDF document text
    • https://annjulieskarpmo.com/userfiles/file/boboxegopivetipen.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/tupexagesozep.pdfIn PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/56181636215.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c4e7dcef441---nobimubikotumimijafoposop.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/17915554324.pdfIn PDF document text
    • http://cosonhuath.com/hinhanh_fckeditor/file/niketar.pdfIn PDF document text
    • http://tanriovermensucat.com/uploads/genel/files/bebabezurijison.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce1b8a7318---jewogukip.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/50pava9ml5h0pi5qap2v3994e0/61785995156.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7014d627214046249b0c57ecd627ab8c/mupesetudebujataxet.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607618b7120f8---64942799505.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b8145280f0f---36020389655.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6205caace---18417468577.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b653a1213---76505162281.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/8724b01319af768ef4779fdc03e9d7b6/82097022964.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=articles+exercises+class+7PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10911 4928 bytes
SHA-256: 8cc8a1d2a7d0b878d2df83dbe034651489d75aeedb1ae64bfaaa039616c8fcfa
font_01_sfnt_off000119ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119EC 11368 bytes
SHA-256: 240c95028bc020fa8b512558b5e8f0c3c9144de85958c21a1d9596f2ca46d496