Malicious PDF — malware analysis report

Static analysis result for SHA-256 c27e9cbb1028a876…

MALICIOUS

PDF

73.6 KB Created: 2021-09-24 11:38:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5606c15a2d64d4060a60a1976cc867d5 SHA-1: 4ae1f09cdcb96dc35a521c1b36b46e161af595a9 SHA-256: c27e9cbb1028a876a1e982b4010872c6c5a8a4848a11a90c130a2c9385ca6a66
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, indicating it is designed to redirect users to potentially malicious websites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to obscure the true destination by using many disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://queure.ru/uplcv?utm_term=differentiate+prokaryotes+from+eukaryotes PDF link annotation
    • http://fisioterapiasuzzara.it/userfiles/files/90750716894.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/woxotuv.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/vazulomobalipufufirize.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/16c3ac1db312b0b2411a97c35c0bdbd2/nokeva.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/doboxepoj.pdfIn PDF document text
    • http://medicareclinichowrah.net/faboriginelist-braj/userfiles/file/88507717966.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1b7431323---mosededijukujexuvikukona.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109071959202379.pdfIn PDF document text
    • http://consorzio-csa.it/userfiles/files/31078981488.pdfIn PDF document text
    • http://dokturmice.com/ckfinder/userfiles/files/3567168145.pdfIn PDF document text
    • https://www.algeos.com/js/ckfinder/userfiles/files/dogir.pdfIn PDF document text
    • https://shatalarab-llc.net/userfiles/files/gidaxit.pdfIn PDF document text
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/vupupin.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/10367565075.pdfIn PDF document text
    • http://tortsurprise.ru/upload/redactor/files/78212923605.pdfIn PDF document text
    • https://www.gpaci.org.br/cms/ckfinder/userfiles/files/woxajomotukinokev.pdfIn PDF document text
    • http://elma1.ru/!upload/files/81534400951.pdfIn PDF document text
    • https://sikahaiphong.com/images/news/files/mupewizebirejo.pdfIn PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/35920032363.pdfIn PDF document text
    • http://whatifitspossible.com/ckfinder/userfiles/files/98746548562.pdfIn PDF document text
    • http://maynenkhiinverter.com/media/ftp/file/16078348518.pdfIn PDF document text
    • https://dananeye.com/uploads/files/202109130846015698.pdfIn PDF document text
    • https://guruvinodji.com/Userfiles/file/78053572564.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210913_220233.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_off0000bd91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD91 10780 bytes
SHA-256: 2ae2a91efa3957223cfea1914c0346a424b0641eb6853ecf0eec044337cb5f62
font_01_sfnt_off0000d675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD675 16864 bytes
SHA-256: c039bb404bead7cdb345ff8da83528a1c44e638ec36afb9d2a841dd2b1169c49
font_02_sfnt_off00010084.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10084 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1