Malicious PDF — malware analysis report

Static analysis result for SHA-256 634eb950f5193a5b…

MALICIOUS

PDF

79.5 KB Created: 2021-08-29 11:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 385a69bc5558b43127d37e7838c5c511 SHA-1: 0725250d3ace82fa7a319b78a06ab3c0549c8af5 SHA-256: 634eb950f5193a5b14075fee41d1e78ee53c65ae8dd32d11b27f3b79f80edc5c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. Several heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution attempt. The presence of multiple unknown URLs hosted on various domains further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/fd64f947b35ebe69f13e944191bb390c/72275875170.pdf In PDF document text
    • http://ktcz.eu/files/files/verifax.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/73365552582.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f30069d13e---faxuru.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/757e72caa37b6730aa2e9ba0a76a70ac/1186673533.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/banarew.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/letusazupebamen.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610c318cf0f33---nevupavujajopuje.pdfIn PDF document text
    • http://tion.hu/upload/file/32314607960.pdfIn PDF document text
    • http://timecraftz.com/userfiles/file/99500155658.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f3ddf029218---jasisedatolijivik.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/a94d1bd1d858896d14ce8373fd1f4ac4/padun.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9d0978ad0---bedifap.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/75495576267.pdfIn PDF document text
    • http://gapp.fr/medias/files/juvezafema.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/xopoki.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/nopibuwajabizagiwexijubir.pdfIn PDF document text
    • http://tanphatinst.com/vietkiendo/upload/file/24275056632.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/a981ce43e6b2a82f146c6daadc81373b/68007504255.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/8008299742.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9199d7cf8---wulewox.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/6tumbq0uatf47fnakcfih6h2n6/39368946175.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/76280303920.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072884f0511c---ritudoxaw.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/795ef1589a774a1cf3cc699db0bcca33/gulutuwovademimon.pdfIn PDF document text
    • https://unosms.us/userfiles/file/zojuwemogalasimuzuzo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=how+to+reduce+pdf+file+size+acrobatPDF 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://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_off0000d2b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eacc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACC 10884 bytes
SHA-256: 7e80cc9758dd0f96662542c95ce456adc4e18a93406e9e1f8322d1ff63909e6c
font_02_sfnt_off000103e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E8 16896 bytes
SHA-256: 45693c922952b76bbaaccd093359be59323fcebb6075c63ab5e48312d786a38f