Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c3913c422a7ece…

MALICIOUS

PDF

73.8 KB Created: 2021-09-16 02:51:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1bc0857a9d90012b75e5d730962786fc SHA-1: d38d38d35eccba8f56fe67055ed1ae6f26c86c0e SHA-256: 31c3913c422a7ecedd34acc812d9acbdac0987680d67c448811b3a6685477601
166 Risk Score

Malware Insights

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

The PDF document employs a social engineering tactic, specifically a browser extension installation lure, to trick users into compromising their systems. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the nature of the lure suggests potential for JavaScript execution or exploitation of PDF vulnerabilities to download and execute further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://k9careclinic.in/ckeditor/ckfinder/userfiles/files/jorakatebul.pdf In PDF document text
    • https://behagi.eus/files/galeria/files/22338996552.pdfIn PDF document text
    • https://shindah.com/images/ckeditor_img/files/xosisi.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/55600842436.pdfIn PDF document text
    • https://maydangson.com/vietkiendo/upload/file/zogulegokomatidejaka.pdfIn PDF document text
    • http://boldogelet.hu/media/vesuxixixijadesupo.pdfIn PDF document text
    • http://alwaditrading.com/userfiles/files/30023054722.pdfIn PDF document text
    • https://aletihad-group.com/userfiles/files/69218919471.pdfIn PDF document text
    • http://kleni.cz/userfiles/file/mixevozavalixoda.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/14359564482.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/puzomodevosozipovupetido.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210914182407.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/zenekukipenuxow.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/nokulasawuda.pdfIn PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/pemorejorolomugowabi.pdfIn PDF document text
    • https://iohrp.org/f_files/files/43237791543.pdfIn PDF document text
    • https://prevodi-plovdiv.com/userfiles/file/rumemisanojedigakanuta.pdfIn PDF document text
    • http://magdrywall.com/project-new/christianbook/upload_images/file/57310741141.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16140ea1411260---najanofatirelevojasulopel.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/bizufitinikezovuziwibi.pdfIn PDF document text
    • http://exosushi.com/uploads/files/kiralovinibevujo.pdfIn PDF document text
    • http://dostavkaturov.ru/files/file/dipekuvibekazo.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/jetukano.pdfIn PDF document text
    • http://sualpturizm.com/userfiles/file/wevul.pdfIn PDF document text
    • http://sksound.com/userfiles/file/jurejeforu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=hnc+sports+live+apk+downloadPDF 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_off0000bcea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCEA 16992 bytes
SHA-256: fc2766dcb2a49a5c24fb2a74aadbbbed21d7c8fad307c3f4aeb5a26d566f1460
font_01_sfnt_off0000e8e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100FB 10744 bytes
SHA-256: 0c8bb88084993e958a527e4e8721d32161d6c981c0656220e6376d173572a31a