Malicious PDF — malware analysis report

Static analysis result for SHA-256 c24c74dc8e2b1daa…

MALICIOUS

PDF

92.0 KB Created: 2021-07-16 05:14:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e4096f8f1343085bf37e0d340ac6247f SHA-1: cafce29004be7ea8548aebeeee7bd30c758c10fc SHA-256: c24c74dc8e2b1daad3e471a06761a7bd1d98c4d4556784f95570ac8716b2896a
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to external sites, including one hosted on a compromised WordPress upload directory. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for hosting links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://beateromer.com/bilder/file/nazedokodunabe.pdf In PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16247010784642.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/gunoz.pdfIn PDF document text
    • https://www.bramfordgc.co.uk/ckfinder/userfiles/files/21385229173.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/modagapapafut.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/acd8d5719cde01d59640a56421faf0b9/84103287290.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16080f969d1585---sesebepetizab.pdfIn PDF document text
    • http://greenld.com/userfiles/19669181702.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/berapuxemorazaxuraguji.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/7249327188.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aeb3a0061a---51625609489.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/880n3391cucj85fbk52ojq6pc6/80160137674.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/oj0q4dbmb2qme60674qpg1d7f9/21803572626.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbd3d0b42f2---belidimisomewopetokadozim.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/790284eb5e388eee007fd4e7212e6c66/92993501571.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/sukavizu.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/uoj0vdg8p118aa1udih25lumd5/87578797285.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/ledaj.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/91032957713.pdfIn PDF document text
    • https://anukulagrotech.com/userfiles/file/63875646256.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a8eed6b01---20793348043.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/vuwasekemapiwidojifasow.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/13evduh4hoctjr7ncflfhd0esb/neriv.pdfIn PDF document text
    • http://perles-del-beya.com/userfiles/file/panogevemokarojoxali.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/vunudanoparibikomalasazal.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/gawevotime.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=mathematical+riddles+for+kidsPDF 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_off000105fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FC 10720 bytes
SHA-256: bb51def7a9d004ab7d397d45bcc7592113829a808aac413fce33622392c62ebf
font_01_sfnt_off00011ea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136B7 16856 bytes
SHA-256: be2eea8596298b5cd1dc5aab1014c9af921b66d071867be47a879b233e2439c5