Malicious PDF — malware analysis report

Static analysis result for SHA-256 82c8f6520f8a9a83…

MALICIOUS

PDF

68.6 KB Created: 2021-10-03 21:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 51c9e461a75754e2e07e81c6674c31ff SHA-1: 0738a8d365286bf7f487d6de67d7823db546f5e0 SHA-256: 82c8f6520f8a9a833b008635e3f3060e381dd140aacb8b8b2f067c1f853944c1
154 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and is identified as a phishing lure, likely intended to trick users into clicking a link. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript is likely responsible for redirecting the user to a malicious URL, which is a common technique for delivering further payloads or leading to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://vcubusinesssolutions.com/userfiles/file/pujojiwixurubimiz.pdf In PDF document text
    • http://thedewakohchang.com/image/upload/File/owododotimozajawo.pdfIn PDF document text
    • http://pi-consulting.ch/download/40331341343.pdfIn PDF document text
    • http://www.msjcongregation.org/www/js/ckfinder/userfiles/files/61778719516.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/16142b8457e23d---zoxuxazosov.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/waxidarazitikubefeg.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/ximoxusu.pdfIn PDF document text
    • http://congtrinhnhaviet.vn/upload/files/vutes.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/82056005022.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/91804913999.pdfIn PDF document text
    • http://furnitura-syndicat.ru/ckeditor/ckfinder/core/connector/php/uploads/files/7770027052.pdfIn PDF document text
    • https://www.tristar-technology.com/ckfinder/userfiles/files/buwifizatut.pdfIn PDF document text
    • https://salvatoredivilio.it/userfiles/file/97695747905.pdfIn PDF document text
    • https://em.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/20659169992.pdfIn PDF document text
    • http://recepti.plovdivweek.com/js/ckfinder/userfiles/files/93738531134.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/a55e6c978b2815e946fade71d1d84c24/17300006898.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/rarirexufewezuzo.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/gazekefidoxirobux.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/11949970516.pdfIn PDF document text
    • http://mabo-meccanica.eu/userfiles/files/75752339990.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/99274584936.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/zijupepixolevuvalub.pdfIn PDF document text
    • https://frigosztufi.ro/ckfinder/userfiles/files/28292156394.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=meaning+of+structuredPDF 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_off0000b125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB125 14160 bytes
SHA-256: 4ba4b55719f6936bd76506869a43bea8c51d75000c6f40088387de784b7735f1
font_01_sfnt_off0000d41e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD41E 10700 bytes
SHA-256: ec6cc494f62110e48d3feb55a54b36871fd3107cffce3cfba532fd6e7d635902
font_02_sfnt_off0000eca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1