CVE-2026-13189: Progress Telerik UI For ASP.NET AJAX

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

In Progress® Telerik® UI for AJAX prior to v2026.2.708, insufficient validation of the language parameter in the spell check handler may allow an attacker to influence server-side file path resolution and trigger unintended server-side requests.

Affected products

• Progress Telerik UI For ASP.NET AJAX: from 2011.2712, before 2026.2.708 (fixed in 2026.2.708)

Published 2026-07-22. Last modified 2026-08-06.