Malicious PDF — malware analysis report

Static analysis result for SHA-256 9143f5ee6411728d…

MALICIOUS

PDF

94.0 KB Created: 2021-10-07 18:43:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 9adefc571094712ebc14c3ad26b4f51d SHA-1: 304514afeee4ba4ebf89a0cf9afe50e4b0078905 SHA-256: 9143f5ee6411728dae5f6e47b36e4d2b0670d86ad4002a8b69ed9f35bf0ef085
166 Risk Score

Malware Insights

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

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it's a phishing lure designed to trick users into installing malicious software by masquerading as a necessary browser update or extension. The document body is heavily obfuscated, preventing a clear understanding of its direct content, but the presence of numerous external links and the 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggest a social engineering attack. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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 http://vivo-mebel.ru/upload/file/34853289644.pdf In PDF document text
    • https://syteq-pro.com/userfiles/file/jaruvexatunizigivijomupug.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/45659230785.pdfIn PDF document text
    • http://highspiritsmusic.com/ckfinder/userfiles/files/1012664917.pdfIn PDF document text
    • http://sibaco.ru/ckfinder/userfiles/files/78560221808.pdfIn PDF document text
    • http://kartelabasligi.com/images_upload/files/kuteguzisumopok.pdfIn PDF document text
    • https://serka.com/serka/upload/files/litadazibuzasunoki.pdfIn PDF document text
    • http://luluscafeonline.com/uploads/files/rekigonudemowemuvubatu.pdfIn PDF document text
    • https://raselapp.com/userfiles/file/gujonakuzitew.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/sojade.pdfIn PDF document text
    • http://flemingdecal.com/uploads/assets/file/61548577176.pdfIn PDF document text
    • http://honmamon-s.com/img_seminar/userfiles/file/17248131828.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158521c7f167---masapuwakedetoru.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/jowadiwokodanegikizugobug.pdfIn PDF document text
    • http://irs-messtechnik.at/upload/xobikovuribebejotibu.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/kivoba.pdfIn PDF document text
    • https://affordans.com/ckfinder/userfiles/files/rovepin.pdfIn PDF document text
    • http://rapet.hu/files/juvutuvulevukaju.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613157563699d---75088651138.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/935648755.pdfIn PDF document text
    • https://ntct-dz.com/ckfinder/userfiles/files/rosalimasilama.pdfIn PDF document text
    • http://gojjang.com/uploads/files/kekadagojesomubin.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/53034358634.pdfIn PDF document text
    • http://chinasoftcore.com/userfiles/file///bunujevivexifimu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=project+expense+sheetPDF link annotation
    • 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_off000109cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109CC 10404 bytes
SHA-256: 9f999c7640f6f3d5c350ef4325b92545c3a1b5d984421c6b9b192f1f1d283b1c
font_01_sfnt_off00012154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12154 18892 bytes
SHA-256: ae05141c0ac5921f61ea360bde4af6003882788b663f1238777185d4fe7dc5e5
font_02_sfnt_off00015234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15234 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1