Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4d59d90ec04652c…

MALICIOUS

PDF

85.5 KB Created: 2021-09-21 04:48:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1eb3d3b86e27e723181726972b94b7aa SHA-1: 58383c1441fea165665d9b92157013ae15577184 SHA-256: c4d59d90ec04652cbd9ed3d700cffc2156191b86cb3b77f0c4d452445aee45b2
126 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm on disposable hosting. The PDF contains numerous embedded URLs pointing to potentially malicious content, suggesting an intent to redirect users to phishing or malware download sites. No scripts were extracted, but the overall structure and URL distribution strongly suggest a malicious document lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://teamcode.net/upload/files/vijubitobu.pdf In PDF document text
    • http://sintjorisparochie.nl/userfiles/file/kamumaribadavemafe.pdfIn PDF document text
    • https://1snrpaulista.com.br/ckfinder/userfiles/files/razebu.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/45024152684.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/20219201646294345.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/76527858464.pdfIn PDF document text
    • https://horkolas-gatlas.hu/ufiles/file/89833714767.pdfIn PDF document text
    • https://yenicekentkaplicasi.com/userfiles/file/sofav.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/silux.pdfIn PDF document text
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/kiviw.pdfIn PDF document text
    • https://lwim-ouargla.dz/ar/files/15899180423.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/taxofibupamabuwowutuk.pdfIn PDF document text
    • http://volker-issmer.de/userfiles/file/lipuriwewuneg.pdfIn PDF document text
    • https://worldtradezone.com/userfiles/file/muwiwugu.pdfIn PDF document text
    • https://fizjolech.pl/userfiles/file/nepele.pdfIn PDF document text
    • http://damvua.com/damvua/public/images/files/xederu.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/31620118680.pdfIn PDF document text
    • http://huefpdf.org/upload/file/23075577070.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/57615429785.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/37669854824.pdfIn PDF document text
    • http://www.buildonhope.org/file/kizoxuboxunagozifab.pdfIn PDF document text
    • http://auto4-spb.ru/public/images/ckfinder/files/zunizew.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161453ed6d4b20---43866934405.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/48103709189.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=no+app+found+to+open+url+on+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_off0000e94d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE94D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001015f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1015F 18260 bytes
SHA-256: b74502d121ddd275611ca84d04bb249bd7db7bcdbe3e72bf6a686daa8f47a8c7
font_02_sfnt_off000130aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130AA 10400 bytes
SHA-256: a330523116572cfefbd89ece50600880b5356ba8812c71afbae9bb7019d03d3b