Malicious PDF — malware analysis report

Static analysis result for SHA-256 f425c2e146c86dfa…

MALICIOUS

PDF

71.4 KB Created: 2021-07-10 08:14:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 4427237496bf1e94745d35216537dd0e SHA-1: aee55249bed455aa906d7b631d1b2715346f9190 SHA-256: f425c2e146c86dfa8fbe79cbbb569fceed9606ecc50025830b99c41fd69b9a86
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the true destination and potentially track user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=outline+of+dairy+technology PDF link annotation
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/395a9b6e8ca68dbc9b48d7663d7e847c/nefopogidi.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/3d9fdef6bac3187ff3652440ebdedc55/nufifesirolilifumuw.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/579f3ebe38b2f630910a0239ae472b97/1558594772.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160774d85066d5---noguf.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/75464235959.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/lemokuwuka.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608709e313b2d---87688984769.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608409aea5869---5311787037.pdfIn PDF document text
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/pb3ijj4skcsunl8e4aoo9rojc7/35686992100.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/d82d93263e988d5481de75ea64500936/bakokowu.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/jopenikiwixijur.pdfIn PDF document text
    • http://pixel-pro.ru/upload/file/kadukubekobu.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737d89b2b8c---rupunobitixuniroze.pdfIn PDF document text
    • http://thayloilocnuoctaihanoi.net/upload/files/kunuv.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e54e54efba---joseludusepet.pdfIn PDF document text
    • http://aostavet.it/userfiles/files/deligalejexogit.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/cis9tnglcan5k6sk2quijsu9n0/vitarigepivisem.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c3d9c1fb98---44276447289.pdfIn PDF document text
    • http://hotelpenza58.ru/ckfinder/userfiles/files/9542062037.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606ceb77751ee---sekawibajuj.pdfIn PDF document text
    • http://harasim.cz/uploaded/files/fuvixute.pdfIn PDF document text
    • http://dzbnf.com/upload/file///jomabirakut.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/b35e69ffc75e681ac239b84609b77694/jaxowif.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210607/1754126786.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_off0000b619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB619 10828 bytes
SHA-256: 91896850c3e2706fc66760f7a031d4b94cc9e7348ecbfbe98b0b4a4ccc3616ab
font_01_sfnt_off0000cedf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F1 15908 bytes
SHA-256: 07e830e28fac59c05daeaf6e5145ae824fa68ce71510db4bfd73f32c3c069590