Malicious PDF — malware analysis report

Static analysis result for SHA-256 748b3ec2902455f1…

MALICIOUS

PDF

83.7 KB Created: 2021-06-13 09:51:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: 864a7d788daa97d790672e8dc3abcb8c SHA-1: 147174c6a0a47b820775bf81ad976e0e44e42ba4 SHA-256: 748b3ec2902455f166ec77b16c4ce6c55c15dbe245aee8347b2522d2b922a1f7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs and link farm heuristics point towards an attempt to redirect users to malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://pistant.ru/uplcv?utm_term=windows+photo+viewer+convert+to+word PDF link annotation
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/oqeaou98mkkqqkte3p0l60i3bm/kuxalu.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/90672745827.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa0819b32f---51877665380.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/98457058243.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/97086825228.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/79484440880.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c5727e2125c---59491668187.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e32c2c8655---zeserejanuti.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16081e2a61cebb---4342705620.pdfIn PDF document text
    • http://coffee33.ru/archive/file/belebunanad.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/8eaa34ff7463a9c379113a60a1cf87fb/legarelanuzo.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/550djq7en8stuh9ldkc9a464a0/wimileronapajejiwetubu.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/49156956948.pdfIn PDF document text
    • https://sambelteri.com/contents//files/14324438912.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/7bc283b3adfbab34f658ff31591c31c7/28220159353.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn 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_off0000f43d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43D 5084 bytes
SHA-256: 2be8dc0702eac3035780a6e7ed584607c268e62836711ec4b190754beadc5a7c
font_01_sfnt_off000105a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A6 11288 bytes
SHA-256: 1217bed0e0b18537fdbf11093dd7b76b9790b131b54a00df2f956febdc7561c3
font_02_sfnt_off00012c58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C58 16076 bytes
SHA-256: 9d161d6e34f835aff196e226d852edde4d65b072a4902c32411b177d8c29261e