Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8848646c1327ec8…

MALICIOUS

PDF

82.9 KB Created: 2021-09-16 08:19:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 23aa6db74a88fa6b91ec23d7c148c68d SHA-1: 72478135617df006528de6ad0f01693c556133f8 SHA-256: d8848646c1327ec869b50ec62e1882dfd505f5f82c851c720c01666f95173041
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains embedded JavaScript and multiple external URIs, with a high ML classifier score and ClamAV detection indicating malicious intent. The 'SE_BROWSER_INSTALL_LURE' heuristic strongly suggests the document is designed to trick the user into installing a fake browser extension or update. The embedded JavaScript likely facilitates this by executing malicious code or redirecting the user to a compromised site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://xn--80ag1a2a.xn--p1ai/files/file/rikimosevezokeziresoxe.pdf In PDF document text
    • http://falegnameriacastiglione.it/userfiles/files/22563376121.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/93145399295.pdfIn PDF document text
    • http://jevades.com/aircraft/fckimages/file/6800602382.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/95793008091.pdfIn PDF document text
    • http://cn-daomeng.com/upload/userfiles/files/a73ef7749f04a2974c22ead2cecfa908.pdfIn PDF document text
    • https://tommytest.dish1314.com/data/html_editor/files/wogetaxeboli.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/numokikugiwodudutoni.pdfIn PDF document text
    • http://sallytour.com/FileData/ckfinder/files/20210902_FC893FA11ABDEA44.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136c527ece82---32229421316.pdfIn PDF document text
    • http://domario.ru/userfiles/file/37297553709.pdfIn PDF document text
    • http://bancasemecanino.com/userfiles/files/25807754443.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/tinuzifigozila.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/zoramajizaxosim.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/58113725691.pdfIn PDF document text
    • http://daechienglishpark.com/ckfinder/userfiles/files/89091122107.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142616ff3a69---34716672545.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/tavisugapovewag.pdfIn PDF document text
    • https://henuopack.com/d/files/19696500575.pdfIn PDF document text
    • http://carszana.com/image/upload/File/23177881542.pdfIn PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/66116776568.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/38087410699.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/34250594077.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=email+to+sms+for+chromePDF 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_off0000ded3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED3 17964 bytes
SHA-256: 4dc63187b2ebe284d0f85e04c29ddaccea12d0acd081c2c07d87ba71fe6a9749
font_01_sfnt_off00010db4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CB 10480 bytes
SHA-256: f644249f2c9d4359c8cd92457474321d74198e60737bac08e9942d814ff8ff08