Malicious PDF — malware analysis report

Static analysis result for SHA-256 d53b38b7d1f452e6…

MALICIOUS

PDF

85.0 KB Created: 2021-09-18 10:59:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 042dafec4718482deffd09c18d4870b0 SHA-1: 36d30de29f2a00043b4cf4e01702105f197f4d74 SHA-256: d53b38b7d1f452e626d6532cb6d26a3adccf7b871a985e101a1b2b844ca9667e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are hosted on disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://studiecarriere.it/uploads/file/xulukufeviwejuxeje.pdf In PDF document text
    • https://majubesar.org/contents/files/rilaxob.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/kajazuwixum.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210918_020919E630F90BEA.pdfIn PDF document text
    • http://potya.com/ravowurexizew.pdfIn PDF document text
    • http://camonetinternational.com/files/file/vavapizanoxope.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613203a665a92---tufos.pdfIn PDF document text
    • http://orem.mn/uploads/files/newagezifitix.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/xidokogorepinono.pdfIn PDF document text
    • http://tolltisztitas.eu/userfiles/files/35245991428.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16145122dbe89e---badinopeko.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebf681f51a---75437642632.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/padodurasijesew.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/buzenu.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/23354267398.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/fizewibabopewopolubuxuwi.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/rt0hrltn3stmfh2q5ms28ktli7/61657249217.pdfIn PDF document text
    • https://tailormade-sales-marketing.com/userfiles/file/vakobutope.pdfIn PDF document text
    • https://kildevangen.dk/files/gositafe.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/21407393359.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/n6g9648nis1992uum94vqctnvs/67895412718.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/55983314171.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=jogos+em+portugues+androidPDF 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_off0000e348.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE348 20296 bytes
SHA-256: 1adc5e7257199ffa29c462fd4c9c95b0550ad8cb3f4030f3fa7614150e2cc682
font_01_sfnt_off00011582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11582 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D99 10780 bytes
SHA-256: 072a1870f01a1374dd80bffd2e89bc5444591de732ef32dcb8e3a6db8bb537b5