Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ca874cbb68ca9cf…

MALICIOUS

PDF

76.4 KB Created: 2021-06-13 16:00:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: a48cdaf7cb62453cf7272d79559b8f83 SHA-1: d305231995d0dfc9ce569a49c5174a90b7c1b031 SHA-256: 4ca874cbb68ca9cfffb0ce944f569a1faa532da518255b3b3f57f38db1195b47
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://nomylo.ru/uplcv?utm_term=sorcerer+guide+dark+souls PDF link annotation
    • http://on-video.com/movies/movie_data/file/62720814798.pdfIn PDF document text
    • http://ekotronic.eu/files/file/73324623867.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a6030556517---9049059469.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088c9848c17b---zuzupusuz.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/51690580016.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/82915749144.pdfIn PDF document text
    • https://webvitamin.vn/app/webroot/uploads/files/27678646539.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/36574395419.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160774eed9ee7f---20677318305.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4939ec5ddc---21046156067.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/f5a34e370c3e570d4f687ffbdf2f2b74/tukuvometimitobamafugav.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/e8d556075915a5b0a0b5a0ab160b808e/83793521042.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/7f09aa45bb0830b13e02be365674cc75/32767355857.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/18568908b1fc269f18cb255b2feb7731/vawupedavumezabixij.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/rexuposinufanubujapox.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/croqpcg9vus8dtd1s8sic8dgbs/bowukudegeb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e200.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE200 4968 bytes
SHA-256: 2495aa3071322c7d76e96d7a6f594cf919726606596e4c67761b0852fd810310
font_01_sfnt_off0000f2e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E6 10500 bytes
SHA-256: 366ed238bb78e0f79d8fbda92f02c3fc9052bf01debe4360984f6b0502d53494
font_02_sfnt_off000116c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C4 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3