Malicious PDF — malware analysis report

Static analysis result for SHA-256 0921cba723ab5ec5…

MALICIOUS

PDF

70.1 KB Created: 2021-05-03 00:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: e92d1c8a671db6b9e69ec8eac4455eb6 SHA-1: 81bdf46c9e0ec530229850fddbb3e2209e6d2c9a SHA-256: 0921cba723ab5ec5889afe64bdba10508a79ae0b1603d2fa5917c7cbb48a0025
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document that contains numerous links to external PDFs hosted on compromised websites. The document body, though heavily obfuscated, suggests a lure related to vehicle sales certificates. The presence of multiple links to potentially malicious PDFs, combined with the ML classifier and ClamAV detection, strongly indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/16070bc918ba21---sipemazubet.pdf In PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160806cfb403e0---xeramuxewo.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/ml3joeu0sahg0shq16k46vsrug/ranexukuwopuzonedobok.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/giwiluxoboranotuvuxopab.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fae7e882c5---nojilobiw.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/6a354cc2gtqp8njhehpkaitdnq/74165668988.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/43c68a66c5b16393578601f69fed02e4/mofakidepob.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/705d12b561669768027a207c341dedd4/puluruleviwimuvuzokeji.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160878aee03664---fupofivur.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/ovku69dsa5pt6gn7ldvpilveue/3693739007.pdfIn PDF document text
    • https://upchealth.net/wp-content/plugins/super-forms/uploads/php/files/7b68eed1fd6f1a19a377d89279b937ed/97610870236.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f375fb3d91---96415307762.pdfIn PDF document text
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/3cbbcf56ec64cc3a4afb690945cca676/vazagawefebitewez.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/cv9VXjIrmdE/uplcv?utm_term=certificat+de+vente+de+v%25C3%25A9hicule+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d430.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD430 5172 bytes
SHA-256: 4c84ede58e00ff8fdf48cdbc6c7d062fbb1461f6be8516524ce5be3544e42b72
font_01_sfnt_off0000e584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE584 11092 bytes
SHA-256: 1d26ac9c3eadfbbcf897ab7a6d1f8185f174038e2ec83a238d7e1459bb03de83