Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b83fa4985d1cb08…

MALICIOUS

PDF

79.7 KB Created: 2021-07-18 05:31:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: c172a57d2922e2ed4a2383c75ea6e1eb SHA-1: 97477ed97171b598b79108225bd9573c68614512 SHA-256: 3b83fa4985d1cb0887f835b8e88eaee1acaee5d0020a9912b65f1acced56449f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an urgency-based lure. 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 0.9960

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://senhewood.com/d/files/xebovojopotaxesexekir.pdf In PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/cd79ae03fb59e4c734aac22fbef602cc/76692729956.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160905b2e82bff---lofowasodobasuwig.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/1dbb488848262aec296e5301410a97c4/pogaxemax.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/kefonobu.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/77953263016.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b48955da4f4---bagefabijo.pdfIn PDF document text
    • http://guitarenko.fr/img/files/sudanitikabitade.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/wazevizanibapesetujesif.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/mefidagibufi.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d8e9ede3e---50045830794.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16084cc6411318---33744337243.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/ef0f0661292f4234e7874e385bfa77d8/6433378606.pdfIn PDF document text
    • https://www.uflo.edu.ar/ckfinder/archivos/documentos/muxedetuvepapevixirevuza.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7d53052c1---76988526473.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/letipabetobavoxojat.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/84034208002.pdfIn PDF document text
    • http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a8f794f350---33155667429.pdfIn PDF document text
    • https://irepairplus.nl/app/webroot/files/userfiles/files/55968774682.pdfIn PDF document text
    • https://tcremich.lu/files/files/debasojulesawel.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccef1bdd6bc---14063408551.pdfIn PDF document text
    • http://phsclassof1970.com/clients/875774/File/gisogobifesof.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/as1uuvfpivp2ki6o84i3n4ql49/padijidukunadibup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=space+drawing+perspective+by+dong+ho+kim+pdfPDF 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_off0000d148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD148 11592 bytes
SHA-256: e86850d85fba41eb185615364a4261d49ee1f62adc223be47ee182a9aee34e77
font_01_sfnt_off0000ec40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC40 17040 bytes
SHA-256: 0d1686220482550b8ee556936a19dc4b053f2b23c289e6d51a49d9c91f73b4d1
font_02_sfnt_off00011918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1