Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8400f19bcb42cbd…

MALICIOUS

PDF

82.5 KB Created: 2021-09-01 13:35:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 704be7cdcca94c889bc9be147616b9d2 SHA-1: 929597cc70334c4eb6f654d00dd321d157839012 SHA-256: f8400f19bcb42cbd05f89e754c6b7ce4a8768957e811d3c9904a6995d40ad14c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://ketchas.ru/uplcv?utm_term=parallel+structure+practice+worksheet+1 PDF link annotation
    • http://msslink.ru/userfiles/files/64612759101.pdfIn PDF document text
    • https://ctapigroup3.com/contents//files/dixuwegorer.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/pigujideloraf.pdfIn PDF document text
    • http://koreadramatour.com/FileData/ckfinder/files/20210807_874B181733C228C5.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/08edee4f228abd07e1fa9c9e7fb257e3/bufitovegukokepuredesut.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/7f6771de94341e99351684698a168d21/12887468588.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/0f7d736ccd21d72082324f7011d16d31/40931132550.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/ui17s8u1paat4vm2kcul77utj9/jowofi.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7eb5d38372---vubesimebazanenifuwuturen.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c79f50819f6---nipokaxafovaxali.pdfIn PDF document text
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/38834923349.pdfIn PDF document text
    • http://gdgom.com/upload/file/210701034728271342fgak9jbvwrmz.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/d12b398e25f89a8dd7fe78647416a4c7/12050741138.pdfIn PDF document text
    • http://yilip.net/userData/board/file/61433355421.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/paseru.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610aef90cc3ce---77643208074.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/3f07bb44b4281ee49c5d9fb11a60faec/87209076553.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160787d761e573---15391094810.pdfIn PDF document text
    • http://anbao.vn/uploads/userfiles/file/32722276618.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3f426e4bd0---zovewodoremibov.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/89443592598.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/vikagejelapab.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/4fim9lb32mv1kqcborr6k5bh04/lefefanodowovereron.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611920621d144---wisilegelujaluzetori.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/56013442303.pdfIn PDF document text
    • http://pwmtqatar.net/userfiles/file/mikujogibinusep.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/tg8qhe4vg361eat2gkgnn9ioj6/25597186242.pdfIn 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://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_off0000de3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE3E 10700 bytes
SHA-256: 7fa18c5f8dceccb34b683781f8699683c5b82370ab9733342e8aa1fda16f4df1
font_01_sfnt_off0000f715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF715 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F27 17384 bytes
SHA-256: e99350082db4bfc2d5bd27d3a2718275ccb0801f2e1eabbd0fb87270b5c0012b