Malicious PDF — malware analysis report

Static analysis result for SHA-256 953db1e5f3f790e2…

MALICIOUS

PDF

69.5 KB Created: 2021-10-01 09:55:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0235102aad66f8d319111ba246bc8f7e SHA-1: bf9b86775ada053d000779b740102effbf0c910a SHA-256: 953db1e5f3f790e2ffb3ce67a7c092ed715d437b074c2dcfb9058ee320803ad8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or engage in SEO manipulation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://krisoc.ru/uplcv?utm_term=how+to+transfer+photos+in+gallery+to+sd+card PDF link annotation
    • http://noithattamphuong.com/upload/files/6726481930.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614047055af4f---tuwafufutilif.pdfIn PDF document text
    • http://senvietsystem.com/ckeditor/upload/files/42908447666.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/46893482100.pdfIn PDF document text
    • http://www.plan.msu.ac.th/ckfinder/userfiles/files/21171726483.pdfIn PDF document text
    • http://asiancfea.org/userfiles/file/53299413272.pdfIn PDF document text
    • https://driftwoodcc.com/userfiles/files/35999048994.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/19237404654.pdfIn PDF document text
    • http://wittymall.com/multimedia/userfiles/file/95073619798.pdfIn PDF document text
    • https://ntiverification.com/userfiles/file/49202749047.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed07b6d234---35802597149.pdfIn PDF document text
    • https://bevasilicones.in/userfiles/file/60098745584.pdfIn PDF document text
    • http://nhasachnguyenvancu.com/Images_upload/files/93941495547.pdfIn PDF document text
    • https://promobryansk.ru/userfiles/files/58690576975.pdfIn PDF document text
    • https://pasarantogel.com/contents/files/14255522102.pdfIn PDF document text
    • http://apvn.info/userfiles/file/12556473390.pdfIn PDF document text
    • http://marketingnews.fr/images/file/zanimuf.pdfIn PDF document text
    • https://gdaniec.com/upload/files/25250097779.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/290cb808caf76217f18fb56220af296f/63499264389.pdfIn PDF document text
    • http://maysoi.com/hinhanh_fckeditor/file/68032433283.pdfIn PDF document text
    • https://www.mmgrowersg.com/ckfinder/userfiles/files/pavoxiveragofofafi.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/9d7c5487787308e1cd9d681006b9e8af/62004484308.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/eb8a73e359da9c056135cad6c57e95f2/46931139146.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/40975a370e38c3efb471d726eaa6a488/wugululopadelirujipenaf.pdfIn 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://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_off0000b10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB10A 15036 bytes
SHA-256: 288199c52f11829262780cf0c3cb560352405d04b9dd41664b24bb3bb5d6bd52
font_01_sfnt_off0000d6d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eeec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEEC 11092 bytes
SHA-256: 7f3e81a01a62e5c0fb314f047cb963b91f0887e6b36a7366ba41df4d6195109e