Malicious PDF — malware analysis report

Static analysis result for SHA-256 422fc7338b1e1fd0…

MALICIOUS

PDF

77.3 KB Created: 2021-07-02 13:45:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 43185f58b247e5b657ce97a364abdd33 SHA-1: d99ba27fd2a18159023abad99d3062d4940d59ce SHA-256: 422fc7338b1e1fd088a837f8e49ef1d865ad935c9595a957d625354096bce81a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites. These links likely serve as a distribution mechanism for phishing or malware, leveraging the compromised CMS upload storage for hosting. The document body is unreadable, but the heuristic findings strongly indicate a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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
  • 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://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f8085e2a66---58301689519.pdf In PDF document text
    • https://narimasu-chintai.net/jcfiles/file/pezavowuzed.pdfIn PDF document text
    • http://splogservice.ru/content/file/verolatema.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/l79gnmtd77vrenungt2o5nl3n7/bomonigofozi.pdfIn PDF document text
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/9673c1e9eee28451d0c6862da118993e/52138532519.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/s2gnn8p2gsfajv6mf32sempjp1/xisafumakatokoxilumef.pdfIn PDF document text
    • http://npxbyy.com/wang3_3_10_27/Upload/Upload/file/2021691022424904.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160af552607a52---59687590979.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/23902744793.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/69481091860.pdfIn PDF document text
    • https://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/fa218444e17ecaa7d29923a9f47f2e37/kexopizes.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc90c485a47---sigorubomureboxagujiti.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607fd233ad45d---44397767374.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/04rmo3f5dm1re74rg4i7qep1he/19661880440.pdfIn PDF document text
    • http://geyikkimya.com/userfiles/upload/file/36497846730.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdd32f3b17---73007693395.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606d17269f921---silabavupeduwek.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/6320392105.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1417e703f---80821757392.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/sigelezax.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c56464cfef2---22876142051.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f9ad49c24---datipinosob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=only+fools+rush+in+ukulelePDF 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_off0000cbec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3FE 17124 bytes
SHA-256: 95c3bface7c50a9cbb33296c70213173562b3c721259370a7a300e402cc85e52
font_02_sfnt_off000110e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110E2 10380 bytes
SHA-256: 4732b6d848202b2afa980b63d2290734d56a4fd8b95eab5fafa0f64f3bc40326