Malicious PDF — malware analysis report

Static analysis result for SHA-256 31d58db35230478d…

MALICIOUS

PDF

76.2 KB Created: 2021-09-22 14:46:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3782eaf761f981f6dae9cea4e1099b0a SHA-1: cfc34666f950f2a72e1fe930f5af617d685c9da5 SHA-256: 31d58db35230478dbfa76c0a97b4272a55a7ee82782a3c39eb14611e9afd97fa
132 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, indicating it's designed to redirect users to potentially malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the idea of a link farm used for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7511

Heuristics 5

  • 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
  • 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://fotofidelity.cz/userfiles/file/75645010407.pdf In PDF document text
    • http://aorganboys.handyfriendship.com/upload/files/detawilipitoxufedifagur.pdfIn PDF document text
    • http://greece-ex.com/images/blog/file/woziditilesegemifikilegob.pdfIn PDF document text
    • https://aymfly.com/aym_image/files/zulimaxupebotox.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/99280107244.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/pisevazituraza.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/3077739050.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1631358178.pdfIn PDF document text
    • http://ever-pioneer.com/upload/files/koxabubu.pdfIn PDF document text
    • https://alaqart.atelierleuthold.ch/userfiles/files/82480624969.pdfIn PDF document text
    • http://suachuamaydemtien.biz/userfiles/file/51361347670.pdfIn PDF document text
    • http://vina2002.com/uploads/files/xiwibonepijuj.pdfIn PDF document text
    • https://aspirans.com/files/file/9420061056.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/70539700986.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/kodilomagajumumoz.pdfIn PDF document text
    • https://majubesar.com/contents/files/wudowuz.pdfIn PDF document text
    • http://tomei4x4.jp/js/upload/files/84633959438.pdfIn PDF document text
    • http://healthywithhart.com/res/file/koxivoku.pdfIn PDF document text
    • https://asfus.net/virgsurv/userfiles/file/63727305705.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d64a16a1b6---73757285874.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/neloj.pdfIn PDF document text
    • http://dytac.hk/userfiles/37157279382.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/74171667598.pdfIn PDF document text
    • https://santa.my/images/users/00000000/files/88597003340.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=oneos+redmi+note+8PDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D8 22760 bytes
SHA-256: 34c1d37753d1d02841583657ae908e48b0f9577c2e75b9820b92fdb1dfc86e02
font_01_sfnt_off000114bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114BB 10432 bytes
SHA-256: 972610ad1a2ed42dcc64ebae4d7c5468334e11e5438441df1196f2926d5e6673