Malicious PDF — malware analysis report

Static analysis result for SHA-256 41f8cf27693a18c3…

MALICIOUS

PDF

77.5 KB Created: 2021-09-17 10:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 51d2d54a590855f134002e04eef547c6 SHA-1: ad9b2f9362876e8aac3f1322f6cdd65924c8092d SHA-256: 41f8cf27693a18c363fb46b143e285443576b36a7826809a31faf09e4dffcfa4
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many of which point to disposable domains or are structured as link farms, indicating a likely phishing or malware distribution attempt. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 4

  • 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=pixel+strike+3d+apk PDF link annotation
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/makiposofuwosolofozup.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/pabazaxopegenugigidire.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/9029483312.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210903224634.pdfIn PDF document text
    • https://jills.reviewz.eu/app/webroot/files/userfiles/files/42593654162.pdfIn PDF document text
    • http://reklamaopole.pl/userfiles/file/mufesaduzemutowi.pdfIn PDF document text
    • http://hzbmsj.com/images/upload/File/nosuba.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/sefumexixepatebupigi.pdfIn PDF document text
    • http://aviteksural.ru/admin/ckfinder/userfiles/files/pujematulomunarikimarezo.pdfIn PDF document text
    • http://stilistspb.online/public/files/uploads/files/bojidoj.pdfIn PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/romometupafumopaxa.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/72458193711.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/05ebd0a1a23fc5e843fbf978f6142d7b/witugosimopivigad.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///36889893217.pdfIn PDF document text
    • http://cl-pub.com/files/files/44686166299.pdfIn PDF document text
    • http://aurangabadptti.com/ckeditor/ckfinder/userfiles/files/jabumupa.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d0ad7257c---fevovivazemedusidi.pdfIn PDF document text
    • http://nano-vip.com/ckfinder/userfiles/files/72851300229.pdfIn PDF document text
    • http://alocainghien.com/uploads/userfiles/file/dogajositasujukuzosiri.pdfIn PDF document text
    • http://hkbroadwin.com/userfiles/13994399583.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/5061293700.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/71070134988.pdfIn PDF document text
    • http://zeci.nl/im/image/nogidanumowakukokop.pdfIn PDF document text
    • http://wanyuantemple.tw/userfiles/file/90035112364.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/mafosokejalozuji.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_off0000c5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5C1 19140 bytes
SHA-256: 9a0e6d602903523a80ee2fd004b340a06947999a09252cc49165887ca15437ef
font_01_sfnt_off0000f80f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80F 10528 bytes
SHA-256: 164c7b979e6915f70543ea4ae713b76bb207ad1cec6971116dc26352fb982e58
font_02_sfnt_off0001103d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1103D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1