Kendo UI for jQuery: Code injection through kendo.init() in data attributes
Summary
Kendo UI for jQuery compiles data-* attribute values with new Function when an invalid JSON object is supplied to kendo.init(). An attacker with low privileges who can control these attribute values can inject JavaScript that runs in the browser of a user who loads or interacts with the affected page. Successful exploitation can compromise confidentiality and integrity of data accessible in that browser context; availability is not affected.
Affected
- Kendo UI for jQuery from 2022.3.1109 before 2026.4.1111 (per CVE record)
- The first affected release has not been established; older versions may also be affected.
Fixed in
- Upgrade to Kendo UI for jQuery 2026.4.1111 or later.
Workaround
- No vendor workaround known.
- Unverified: a strict Content Security Policy without 'unsafe-eval' may block the injected code. Test this before relying on it.
- Restrict who can write content into data-* attributes and sanitise user-generated HTML before it reaches Kendo markup.
Exploitation
- No public proof of concept found at the time of research.
- No known exploitation in the wild found; CISA KEV status not verified.
- NVD status at research time: Awaiting Analysis.
Our recommendation
- Inventory all Kendo UI for jQuery instances and versions, including bundled copies in third-party apps.
- Upgrade to 2026.4.1111 or later and treat earlier versions as affected.
- Review whether untrusted users can write data-* attributes or markup rendered by Kendo UI, and prioritise those applications.
- Check the Telerik advisory and NVD again in a few days for updates.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Telerik Security Advisory CVE-2026-124686 www.telerik.com
- CVE Record CVE-2026-124686 www.cve.org
- OffSeq Radar CVE-2026-124686 radar.offseq.com
- Snyk kendo-ui-core package security.snyk.io
- Telerik CSP support feedback feedback.telerik.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 17:21.
Original description (NVD)
In Progress® Kendo® UI for jQuery versions prior to 2026.4.1111, kendo.init() compiles data-* attribute values with new Function when an invalid JSON object is supplied. An attacker with low privileges who can control these attribute values can inject JavaScript that executes during declarative widget initialization when a user loads or interacts with an affected page. Successful exploitation can compromise the confidentiality and integrity of data accessible in the user's browser context. The issue was reported in version 2022.3.1109; the first affected release has not been established.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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