Malicious PDF — malware analysis report

Static analysis result for SHA-256 e227045db067b86a…

MALICIOUS

PDF

82.6 KB Created: 2021-09-21 01:45:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1833f47283e920205e2d7ab9acb3190a SHA-1: 8ce00f7ad6cb24a658f9a8a6931706c0e260dc0d SHA-256: e227045db067b86aeb8e17e0286decf3b16b2b38f405a9235fc5474e0d665ee8
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and is flagged by ML classifiers and ClamAV as malicious. A critical heuristic indicates a 'Browser extension / update installation lure,' suggesting social engineering to trick the user into installing malicious software. The document body is heavily obfuscated, but the presence of JavaScript and the lure heuristic strongly indicate an attempt to execute further malicious code or steal credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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 http://idolyokocho.com/js/ckfinder/userfiles/files/20926948177.pdf In PDF document text
    • http://tcsklife.com/filespath/files/20210912233602.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/17983132535.pdfIn PDF document text
    • https://ngenadmin2.nextgenphotosolutions-beta.com/app/webroot/files/file/nutasowinudedamibipujes.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca91dc9b54---84893717708.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/79822844896.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/8255907523.pdfIn PDF document text
    • http://npi-management.org/ressource/site-image/files/75099506563.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/rafimumomen.pdfIn PDF document text
    • https://conrays.ru/f/data/3921934028.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/53767886602.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/zogidif.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/subisaliw.pdfIn PDF document text
    • http://colorsoftexas.com/ckfinder/userfiles/uploads/jomumuri.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/loweb.pdfIn PDF document text
    • http://sziszolg.hu/editor_up/63661799153.pdfIn PDF document text
    • https://vasutaszeneiskola.hu/ckfinder/userfiles/files/tidenesiveg.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/vutagureperosubufofujo.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/lodipomogulej.pdfIn PDF document text
    • http://claudiamelchior.it/images/file/79197016180.pdfIn PDF document text
    • http://chongqinghaohong.com/upload/files/39382297393.pdfIn PDF document text
    • http://aa-nusd.jp/47608571071.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161473490a714c---61739429753.pdfIn PDF document text
    • http://kcde.kr/userfiles/file/29740298675.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/51235584224.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=clipboard+in+android+mobilePDF 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_off0000df36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF36 10460 bytes
SHA-256: 3389999a74c3ce33536e003de67fa74bceb838130f399e05b343fe800a374f20
font_01_sfnt_off0000f694.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF694 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ea6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA6 17812 bytes
SHA-256: b45a57da091b01079522b2f67a5aac428cc16c05447f2f64061da2cd3f256660