Malicious PDF — malware analysis report

Static analysis result for SHA-256 a61697a1dfefc91a…

MALICIOUS

PDF

72.7 KB Created: 2021-06-08 04:59:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 3737463245bd2132a39681beb8f3406b SHA-1: 25211606c3c48702db16161ab6039604d6a344b0 SHA-256: a61697a1dfefc91a7d11b9e8c5857c8f0da0e9217f326639050ab235c7534e5c
96 Risk Score

Malware Insights

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

This PDF document contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm or redirection scheme. The ML classifier strongly indicates maliciousness, and the presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this. While no scripts were explicitly extracted, the PDF structure itself likely facilitates the redirection to these external resources, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://cructi.ru/uplcv?utm_term=how+to+cash+in+my+birth+certificate+bond+uk PDF link annotation
    • https://ascinfratech.com/clientprojects/trading/file/pujefinomewuxatix.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/6786714d8c18de73371e9e2d1d766b9e/sevuniziladorunufo.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076b9e660ba9---mebolobaja.pdfIn PDF document text
    • https://ystechpro.com/nbloom/fckuploads/file/91177064166.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/53703469041.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/11s7ll8o6nd22senekofqlts56/kisebijuzez.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/76fb09cb7f15cae2a57c4f3acc6e777e/14147748350.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/16085750054002---74791934166.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16087ef1ee77e2---pibovexiwup.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/1seogl8ic215ar0c4fcji75ea0/jaramotigirobinom.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/45940389645.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a6f9d65329f---67604874928.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4c86d339e---72854968951.pdfIn PDF document text
    • http://dwhs79.com/clients/15834/File/waxabenofisegozebego.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16081649614af9---dotazibasoki.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_off0000d21c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21C 5468 bytes
SHA-256: 8b61818547f25624269e7370cdafd8776437643edf088143533613cde54e968d
font_01_sfnt_off0000e48d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE48D 10244 bytes
SHA-256: 1fcf7c3989f530fab25de527ddcee84505923176e1059791714b464b3f7f8c1e
font_02_sfnt_off0001079f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079F 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3