Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a7e752a4d2afd2…

MALICIOUS

PDF

92.1 KB Created: 2021-06-26 09:18:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 32fcd2f6f051dac294c424b52d9caf36 SHA-1: 0dbc76a548e26f4f8cc1fc0735ab190e604a4791 SHA-256: a5a7e752a4d2afd2583c3f7a5b5a0abac6bdffe66107f3a7797ddf2412002f86
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting it's designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, and the presence of a link farm on disposable hosting further supports a malicious intent. No scripts were extracted, so the exact payload delivery mechanism remains unclear.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607549adab22b---tikatew.pdf
    • http://dlt-nkp.com/fileupload//file/sijubedapewifomategozu.pdf
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/19egp6apm9n58gusm0qt3lvoo7/fikajivivuwuwafopadenuxiw.pdf
    • http://eurogeographyjournal.eu/admin/fckfiles/file/73664633797.pdf
    • http://www.rodnolespropertymanagement.com/siteuploads/editorimg/file/71334883309.pdf
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/ba7edad761d9f9c2af92d88f0e1ecd84/28606999223.pdf
    • https://rrr71.ru/upload_picture/2544930377.pdf
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/p0ikuqei9ic7cvp95psktoqba5/betidarosogarojuredulupo.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160becc918253e---6881459385.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/871e05df1dc3f3372bb972f6d6c1f6c3/94749518386.pdf
    • http://matsonconstruction.net/userfiles/file/72575206453.pdf
    • http://euro-ex.com/images/blog//file/51606801202.pdf
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/df5bb980b57475ad18c76ae494a1dcad/49620284974.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/93f318f911f828a2d21b11fb15056f39/lexewamikolegidid.pdf
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/045343a53bb9d5015098ee9763786252/21636170959.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16084ae51be291---milobipufos.pdf
    • http://alexanderkanevskyartgallery.com/clientMedia/file/22092407914.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/9dr0oft2krg41ia4e5mv5hefse/volopelimo.pdf
    • https://monyetjoget.com/contents//files/22659231545.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095d0e9ad748---wonasulopojufikokuvojikem.pdf
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a20a9801abd---zibakobaledukovebukanilo.pdf
    • https://mattress-leader.com/media/16952532273.pdf
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed39aad1e6---mokokawonerodiwesasegu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=structural+engineer+cv+pdf
    • 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_off0001048c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1048C 16792 bytes
font_01_sfnt_off00011ca3.bin
26003b9e69db322ca5dec73880aef73bc6967d43d331716a80ce246922e72141
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA3 10748 bytes
font_02_sfnt_off00013544.bin
8eb67fc0f3f69213477ab15b54d3707ee24758b3ed1056fb975f893bbb0969cc
pdf-font-stream PDF embedded font (sfnt) at offset 0x13544 17564 bytes