Malicious PDF — malware analysis report

Static analysis result for SHA-256 b31c60e5b632cc50…

MALICIOUS

PDF

77.8 KB Created: 2021-06-13 02:28:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 3985bb1abbe3e6f2c8c0010c8018e555 SHA-1: 0fe8aa04c24e88c3d8dc8c9f206c17aa3372b54a SHA-256: b31c60e5b632cc50710472cdf7c442a64d190537dcf53b1a1d6a622200a589c8
156 Risk Score

Malware Insights

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

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 0.9998

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 https://crewmak.ru/uplcv?utm_term=horror+movies+tagalog+version PDF link annotation
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e86e2288e---85032183690.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7cdc26d92---65478589139.pdfIn PDF document text
    • http://perles-del-beya.com/userfiles/file/wagibulutufebew.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160a74d32ad98f---bipuwosebanabufil.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160805924aaa8a---32739210701.pdfIn PDF document text
    • https://dm288.com/slicice/file/kabijen.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/39776329368.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/8d9d42c4b797d1303051de3e999d1cbe/jebesosaweroxir.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/7l29i2b5b8odgjlahv27isgcj0/nusabixe.pdfIn PDF document text
    • https://pensiunea-escape.ro/ckfinder/userfiles/files/sotivawudizasozemadalazun.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160985559dc3f8---velitaxudifesimadus.pdfIn PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/27558888581.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/aa1b4dcdaed231353843a08e7b052776/10457353786.pdfIn PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/16op1rmudrqg6760pgvmu9smfs/1031555249.pdfIn PDF document text
    • http://topas.lt/userfiles/file/ruzejukilapano.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/an7su6d7n51cg92ikbicip6vb2/pedajuluzosemonogo.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f25b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25B 5024 bytes
SHA-256: d0573961287d32135da825118e54f573bd770ea773f573264fc9ee4790ec042e
font_01_sfnt_off0001035d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1035D 11656 bytes
SHA-256: 2db39f939dd5f0b0ee56de750a51bb92573815a7a30c5d7e8fd430e751e5788a