CVE-2026-106148 in Kendo UI for jQuery
Summary
by MITRE • 10/15/2026
In Progress® Kendo® UI for jQuery prior to 2026.3.1015, the TabStrip, Menu, and PanelBar components insert data source imageUrl values into single-quoted image src attributes without proper escaping. An attacker who can modify an image URL can inject additional HTML attributes, including event handlers, and execute JavaScript in a user's browser when the affected component renders the image. Successful exploitation can compromise the confidentiality and integrity of data accessible to the affected application. The earliest affected version has not been confirmed. This issue is fixed in version 2026.3.1015.
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Analysis
by VulDB Data Team • 10/15/2026
The vulnerability identified in Progress Kendo UI for jQuery versions prior to 2026.3.1015 represents a classic Cross-Site Scripting (XSS) flaw rooted in improper input validation and output encoding within the TabStrip, Menu, and PanelBar components. These user interface widgets are designed to render complex interactive elements by processing data sources that may include image resources. Specifically, when these components construct HTML markup for images based on provided imageUrl values, they embed the value directly into single-quoted src attributes without applying necessary escaping mechanisms. This lack of sanitization allows an attacker who has the ability to influence or modify the input data source to inject arbitrary HTML and JavaScript code. The core technical failure lies in the assumption that image URLs are safe strings, ignoring the possibility that a malicious actor can craft a URL string that breaks out of the attribute context by including closing quotes followed by additional attributes such as onerror event handlers.
From a technical perspective, this vulnerability aligns with CWE-79, which describes Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting. The specific mechanism involves DOM-based XSS where the malicious payload is executed in the victim's browser upon rendering. By injecting an attribute like onerror=alert(1) into the src property, the attacker ensures that when the image fails to load or during the parsing phase, the embedded JavaScript executes within the context of the vulnerable application. This execution environment grants the injected script full access to the Document Object Model (DOM), cookies, session tokens, and other sensitive data associated with the user's current session. The vulnerability is particularly dangerous because it affects multiple high-visibility components that are frequently used in enterprise dashboards and administrative interfaces, increasing the potential attack surface for web applications utilizing this library.
The operational impact of exploiting this flaw extends beyond simple script execution to significant compromises in confidentiality and integrity. An attacker can perform actions such as session hijacking by stealing authentication cookies, phishing users by injecting fake login forms or deceptive UI elements that mimic legitimate application interfaces, or defacing the application's appearance. In scenarios where the vulnerable components are used within privileged administrative panels, successful exploitation could allow an unauthenticated or low-privileged user to escalate their privileges and perform unauthorized actions on behalf of other users or administrators. This undermines the trust model of the web application and can lead to data exfiltration, manipulation of stored information, or further lateral movement if the compromised session provides access to backend systems.
This incident is also relevant to MITRE ATT&CK framework techniques related to Client-Side Scripting Injection (T1059) and specifically Cross-Site Scripting: Stored (T800) if the malicious URL data is persisted in a database, or Reflected XSS (T602) if it occurs via request parameters. The ability to inject event handlers allows for persistent attacks that do not require immediate user interaction beyond loading the page containing the vulnerable component. To mitigate this risk, organizations must upgrade their Progress Kendo UI for jQuery libraries to version 2026.3.1015 or later, where the developers have implemented proper escaping and validation logic to ensure that special characters in imageUrl values are neutralized before being rendered into HTML attributes. Additionally, implementing Content Security Policy (CSP) headers can provide an additional layer of defense by restricting the sources from which scripts can be loaded and executed, thereby mitigating the impact even if a similar vulnerability exists in other parts of the application stack. Regular security audits and static code analysis tools should also be employed to detect such input validation weaknesses early in the development lifecycle.