Malicious PDF — malware analysis report

Static analysis result for SHA-256 99f6ec1793bc56dd…

MALICIOUS

PDF

83.2 KB Created: 2021-09-22 14:33:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 82a2170b43cc04e54ee0075e7f1f759f SHA-1: 3439aad6a54852989761f24139fc70c912dea253 SHA-256: 99f6ec1793bc56dd8af00fe9a6441916b33807aa14ccefd5372688d30e33e70b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, suggesting a link farm designed for malware distribution or phishing. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of 'utm_term' in one URL indicate an attempt to manipulate search results for malicious purposes. While no scripts were directly extracted, the ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://chcial.ru/uplcv?utm_term=periodic+table+image+pdf+download PDF link annotation
    • http://softwarefactory.nl/images/file/kunupigu.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/881593604.pdfIn PDF document text
    • https://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/saxokuvideda.pdfIn PDF document text
    • https://giyimkent.formenemlak.com/upload/ckfinder/files/kisedikibe.pdfIn PDF document text
    • https://makiriaszto.hu/ckfinder/userfiles/files/tomenufosujunebij.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161382a0e15cf1---nukokozemunazebinus.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/75636360549.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/32999900079.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/jimexumonepixarukos.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/517083425.pdfIn PDF document text
    • http://haitrungkim.vn/uploads/userfiles/file/budewapixakazozoxaz.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/90659076931.pdfIn PDF document text
    • http://bodegaadrover.com/userfiles/imagenes/27255646726.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/jaxafo.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/dololoxamaseloweberiboxi.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/tagewiweb.pdfIn PDF document text
    • http://mytrangroup.com/uploads/userfiles/file/14565102206.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/86360002280.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/nejavibugorivepobuvenix.pdfIn PDF document text
    • http://winteringlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/judid.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/rerisamomuwafanov.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148539d2d13c---76102164547.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/98558603011.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f544a8f104---59658048479.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_off0000df2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2B 18188 bytes
SHA-256: dc6afbb466b7252c136ef9a2af761f2486351a84e6934558a5337bcd270da10d
font_01_sfnt_off00010da9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C0 11020 bytes
SHA-256: 68fdc9b1461f010c634bb14346b388d5ccbbcc6ce14f6a24574f4fba772d0578