Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5897c3c3649a27c…

MALICIOUS

PDF

69.1 KB Created: 2021-09-29 11:15:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 210dbc24518fad96156408b51f3953b2 SHA-1: 1fa6b7eee6c0fc414d41aea2ad4a40f42305fbd0 SHA-256: a5897c3c3649a27c5e85962afd4a59a89d3a870c26c02666d73338d4860250b7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with high confidence. It contains embedded JavaScript and a link farm pointing to multiple external URLs, some hosted on compromised CMS platforms. The presence of JavaScript suggests an attempt to execute malicious code, likely to facilitate further compromise or phishing. The link farm structure indicates a deliberate effort to obscure the final destination and potentially distribute malware or lead users to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://sheilahancock.net/blogfck/file/68033302523.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/61a82f56eeda8f7bff3ab9b9029776fb/41707873096.pdf
    • http://baltic-rt.ru/ckfinder/userfiles/files/xafezubawur.pdf
    • http://gazomotor.com/allinone/file/79244006573.pdf
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72242378379.pdf
    • http://cnpair.com/userfiles/file/rezipi.pdf
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/17923574947.pdf
    • http://yibetter.com/data/files/70795479258.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613983f136bae---58761864266.pdf
    • http://chiaranannini.com/userfiles/files/92312443125.pdf
    • http://escritacontabilidade.net/fotos/news/file/tinaxitonozosepow.pdf
    • http://nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/nuvipakefuxuwanelabifofa.pdf
    • https://aspit.ro/imagini_ws/50785493340.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16152760308df0---51439898093.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161302f8e87aa0---32147032366.pdf
    • https://aashianarealty.com/file/towavesanitapuwilomere.pdf
    • http://hotspot-usa.com/js/upload/files/32246166406.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161401ad541585---kenuz.pdf
    • https://rux-thai.com/ckfinder/userfiles/files/49319271455.pdf
    • http://worldtrip-eng.total-flame.com/application/views/blog/userfiles/file/36367332992.pdf
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/govopujofikokimivibi.pdf
    • http://kelkenaghshband.com/app/webroot/img/files/25127112269.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=videoder+apk+download+old+version
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b0c4.bin
ba70bfed431f0ac7a7cbf81a8e5ae343ddf2ba83ce689b046f8a6e20409efd60
pdf-font-stream PDF embedded font (sfnt) at offset 0xB0C4 10500 bytes
font_01_sfnt_off0000c8c7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C7 16792 bytes
font_02_sfnt_off0000e0d9.bin
530e40a55ee5e4ceb2c2c6959cd93f3d44fd7be4823faae000c6f998dbc94deb
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D9 15124 bytes