Malicious PDF — malware analysis report

Static analysis result for SHA-256 239c59ffb584ec98…

MALICIOUS

PDF

68.9 KB Created: 2021-09-29 04:23:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6c48080711491aa19bfccb1a04c0a470 SHA-1: 2c77e6da3db35223f534cdab88a6a27df3a8c6cb SHA-256: 239c59ffb584ec989046d51b825ba405156e99f4d7b378dfe5f4f95d958376f5
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, pointing to numerous URLs hosted on compromised CMS upload directories and disposable hosting. These links likely serve as a distribution point for phishing content or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb8350bbc9---9616699422.pdf In PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/d276f9fe73a7a2ccc60ba176d5bfb6a1/20567595534.pdfIn PDF document text
    • http://macro-e.com/app/webroot/userfiles/files/27253389252.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/lotepumupubavopovuj.pdfIn PDF document text
    • http://studiotravenzolo.it/userfiles/files/4914027543.pdfIn PDF document text
    • http://steffis-strassladen.de/userfiles/file/46223622510.pdfIn PDF document text
    • https://brakos.it/file/siwazazasopimir.pdfIn PDF document text
    • https://healthlantern.com/ckeditor/ckfinder/userfiles/files/somaponobidunemupek.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/mowuguxedumerubon.pdfIn PDF document text
    • http://tencanpowder.com/d/files/sazorerekadimabizive.pdfIn PDF document text
    • http://doggystylzgrooming.com/admin/photos/file/nidaduzokoso.pdfIn PDF document text
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/kiwupubuvebobofuxoxala.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/64319828096.pdfIn PDF document text
    • http://wakabaeducation.com/userfiles/file/7985871593.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/kuvunijixip.pdfIn PDF document text
    • https://sadhankendra.org/erc/media/luremofowope.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/21904960924.pdfIn PDF document text
    • https://gamepinleri.com/calisma2/files/uploads/29726024521.pdfIn PDF document text
    • http://hansungid.com/userfiles/file/63384499213.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/40729357346.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614bb293d58b3---nagebelupag.pdfIn PDF document text
    • https://tauthuy.vn/upload/files/29222387561.pdfIn PDF document text
    • http://perevodvnegiloifond.ru/pict/file/juzilolodapowe.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161371a11178d9---tefaligutebujew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=currency+converter+code+in+androidPDF 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_off0000afeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFEB 10460 bytes
SHA-256: eb4b583fc506e52e12c0a2ce6825f92f8ebc08584fd64b364b94265a7926909b
font_01_sfnt_off0000c7d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D2 15088 bytes
SHA-256: e8e6fe52c5b88674842ac5917d6ae50092b3cdf9919c2be152a4dc80daa3f924
font_02_sfnt_off0000ee1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1