Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f88781ffc973ee…

MALICIOUS

PDF

95.2 KB Created: 2021-07-15 19:27:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 073ac781110a87b021758631f885298c SHA-1: f1400cad9521f6e111d78e0fd67559eaca1769d0 SHA-256: d1f88781ffc973eef3976437c84ffeed967922e89792d1411e7d09ef01fc955e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the nature of the links and the PDF structure align with common techniques for delivering secondary payloads or redirecting to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 6

  • 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.
  • 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://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3bdf66f85e---45331543812.pdf In PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/o9va00i7doh59gahac9nmojcoe/togesifagodevowa.pdfIn PDF document text
    • http://travelport.pl/userfiles//file/86815496106.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/408504de51c80e0558bf292e260c4a3b/20113541937.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/43854101167.pdfIn PDF document text
    • http://accessoriesunlimitedinc.net/catalog/file/28506522943.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/94789944338.pdfIn PDF document text
    • http://mastervgtour.by/var/upload/file/fexegegokivuxukezo.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/51a16f04c6648a47fbd877875ee0e6ce/sulupewejemuxevujada.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160defd05ef95e---puxenak.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/dd663e8064500c41ac1390c667f3276a/vidadadigipujemetiw.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/jerikamilirulanefi.pdfIn PDF document text
    • http://eaeocs.com/clients/c/c7/c75ed17bfa54634cfc1039f1b599a7e7/File/zinavisipezib.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/dumezamowebafan.pdfIn PDF document text
    • http://canavesiobruno-architetti.it/userfiles/files/sarofe.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b54e4c648a---32159755139.pdfIn PDF document text
    • http://kavtas.com/images_upload/files/24033510811.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/8121196834.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7b7ea8761---8184873772.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/32659131499.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/wotonup.pdfIn PDF document text
    • http://xn--22c6buakeib3ax0bzcc5b8tlc.com/userfiles/file/sigud.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef53553471---jazezutejerudobixirigixag.pdfIn PDF document text
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/tegizukubuzolub.pdfIn PDF document text
    • http://klefmarken.se/upload/file/93890733422.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=volunteer+questions+and+answers+for+interviewsPDF 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_off00010fb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB5 17848 bytes
SHA-256: 18edc9c07f5a727c7f29da428350baee12aff8a51fd17bf36e6c22c254fbee76
font_01_sfnt_off00013e8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000156a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156A4 10716 bytes
SHA-256: 7344f212b17ba4a33d2f9061844d889bc2b787f983a51d3f1d9f95d822598d62