Malicious PDF — malware analysis report

Static analysis result for SHA-256 003d86fb6ba5e732…

MALICIOUS

PDF

81.5 KB Created: 2021-09-13 18:42:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 106fd56e3239340ab8367c37ae4e579f SHA-1: fe57ba7e53facb4edb0e38e160d74ad54b710d24 SHA-256: 003d86fb6ba5e732f8e7800f20c7cf56e032bcf0fe84907232b9a7122a6b2e85
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with heuristics identifying it as a link farm hosted on disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically phishing. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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=best+sleep+cycle+alarm+android PDF link annotation
    • https://rtquery.reitoken.org/Coaching123/images/files/23445403224.pdfIn PDF document text
    • http://contelex.it/userfiles/files/83604828011.pdfIn PDF document text
    • https://izometal.net/mm/file/55041728761.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/1360536889.pdfIn PDF document text
    • http://hondatayho.top/img-ngocbao/files/28266510315.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/97856606983.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/jegimidefat.pdfIn PDF document text
    • http://gestioniarmatoriali.it/97164843240.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/54428999418.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/67666982825.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/tadubuxawojerosoforel.pdfIn PDF document text
    • http://daindnc.com/fckeditor/userfiles/file/51206784190.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210902_011943.pdfIn PDF document text
    • http://landpas.pl/upload/file/doteguluvapowonanak.pdfIn PDF document text
    • https://tapuionoticias.com/ckfinder/files/rofajuluniputa.pdfIn PDF document text
    • http://hanauhrova.cz/files/59423021081.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/34887266854.pdfIn PDF document text
    • https://ags-car.com/upload/files/71617960378.pdfIn PDF document text
    • http://inbond-cn.com/userfiles/file/domeganunenexojikapeneluw.pdfIn PDF document text
    • https://stthomasorthodoxchurchsouthpampady.com/userfiles/file/vazet.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f823573529---5833807577.pdfIn PDF document text
    • http://vititanon.com/user_img/files/65774523205.pdfIn PDF document text
    • http://chinazzjx.com/d/files/kodixigepawanebada.pdfIn PDF document text
    • http://ekorepetycje.eu/Upload/file/27729350703.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_off0000d847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD847 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF059 18076 bytes
SHA-256: 4e6b7f5ebcd541cb544ea5ae94f22e5c0f4567e60ea167d5739468d7f59de2ba
font_02_sfnt_off00011f0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0C 10840 bytes
SHA-256: 3f87cd83f395922fd2e4ad6ddb007cfe448da191a3385759ab4dd0786c45caf6