Malicious PDF — malware analysis report

Static analysis result for SHA-256 52ced359fa073da5…

MALICIOUS

PDF

80.8 KB Created: 2021-09-06 15:02:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: fe5c9494531f9dbaa3739c3f2ab53f8b SHA-1: e78ce32ef52121d6a75ea1a3b548742eb98d2302 SHA-256: 52ced359fa073da5ffe5fb2caabdd9d3dfa18066df75e4ce0c4bc2d7011fa0f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16085535ba584f---15130993099.pdf In PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f6e4f2d95---terawatuteneta.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/tebizut.pdfIn PDF document text
    • http://zjqzzx.com/uploadfile/file/2021070100575073499.pdfIn PDF document text
    • http://eternoohydro.com/d/files/pizudajini.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/pavuromebevetogovetika.pdfIn PDF document text
    • https://combrooncom.com/contents//files/tiwusu.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/dovixijevoragofuvik.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/gg4roaj5r99abr51hgqa214lc8/85938217860.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b44b7744b---55596422046.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/budogoberodagifuvi.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/cfgsfs6a3r4iqu5n33c14bea94/zepakijer.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/42841165418.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/c79765f2ad80de070f195117dac79574/52918323472.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/70969789884.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/ig1vsuo24j61c6vs8tp4mos5o6/jejokonuw.pdfIn PDF document text
    • http://menloathertonhigh1980.com/clients/6/6f/6f83464fe0b13873896cace574d4baa5/File/99087143736.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/vemadabijiwiwodute.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/pirokovodatadivel.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16083cad83247f---45492657499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=addition+and+subtraction+worksheets+pdf+kindergartenPDF 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_off0000d645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD645 11252 bytes
SHA-256: 843ea3da22d042ca37ab2d696b7259754b780d7e7d332a674c66b978c6baf4ea
font_01_sfnt_off0000f050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF050 17412 bytes
SHA-256: d05ee47cd8adca3120b3c63490e6d7570cdf33f9e98494a53be324e27f0eb04a
font_02_sfnt_off00011d7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1