In Progress Kendo UI for jQuery, Spreadsheet sheet names are inserted into the SheetsBar menu button's data-sheet-name attribute without encoding. An attacker who can influence a sheet name can inject an event-handler attribute and execute JavaScript when a user hovers over the menu button. Successful exploitation may compromise the confidentiality and integrity of data available in the user's browser context. The first affected version is 2024.4.1112; the latest vulnerable version is 2026.3.1015. The issue is fixed in version 2026.4.1111.