Malicious PDF — malware analysis report

Static analysis result for SHA-256 b75e4d51b39834b1…

MALICIOUS

PDF

85.9 KB Created: 2021-09-17 13:09:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f5ca75b43b9ab0c30a6b4b871dc87988 SHA-1: ecf5c1011ee0bd5b8c9a5950413487e869533ec1 SHA-256: b75e4d51b39834b1dc42aae02ef93f1367f1e4fe3d847dc9a01785e3929f827e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is identified as a link farm, with many pointing to compromised WordPress upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with malicious PDF lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://philabc.ru/uplcv?utm_term=windows+7+print+to+pdf PDF link annotation
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613d018870f1f---67871888019.pdfIn PDF document text
    • http://associazionemillesogni.it/userfiles/files/notaganudi.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/161302d5b55652---selufewugoxejewuxujojin.pdfIn PDF document text
    • http://interroadholland.nl/userfiles/file/fejulojagubuto.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210910_9BADAD9E2733C5E1.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d73c4ea48e---96576985796.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd0db30175---gojedewidagaweroviwilipil.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3650cdf41---44624748058.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/wutasibijarinorizanu.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/xedasamusijajuzomujaxof.pdfIn PDF document text
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/15287243806.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109061131037047.pdfIn PDF document text
    • https://trainova.com/userfiles/file/fokezidopererurexozixodi.pdfIn PDF document text
    • https://colakcivi.com/userfiles/file/70237452890.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/90973467443.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/6e1e796c5f5d1adb2433afb98a11ede3/10997545987.pdfIn PDF document text
    • http://elitk.ru/_files/ponavajamazatumiwa.pdfIn PDF document text
    • http://s13cf5ef.alojamientovirtual.com/ropalaboralbarata.com/userfiles/file/kubapapuwe.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/27764936729.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/66924215778.pdfIn PDF document text
    • https://digireg.ru/upload/75639033048.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_off0000ebf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF3 18120 bytes
SHA-256: 773f81f487bb950e133b5a9cd99402447eb07c59ced96b9756baa8603790361f
font_01_sfnt_off00011aeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AEB 10280 bytes
SHA-256: f0d3b9b1fca42c0782e0cf50613b9f5bbf570f0731dff57d9b7f2c1f4533bfa2
font_02_sfnt_off0001323a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1323A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1