CVE-2026-106155: Stored Cross-site Scripting (XSS) in Telerik Report Server Web Report Viewers

Severity: high (CVSS 8.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-09 · updated 2026-10-09
Weakness: CWE-79

Description

In Progress® Telerik® Report Server prior to version 12.2.26.1007, a stored cross-site scripting vulnerability in the shared reporting engine allows an authenticated report author to embed javascript: or vbscript: URLs in report navigation actions or HTML text box links. When another user views the malicious report and the embedded navigation is triggered, attacker-controlled script can execute in the web report viewer's origin. In a multi-user Report Server deployment, this can enable privilege escalation by performing actions in a higher-privilege user's authenticated session, including an administrator's session.

Affected products

Progress Software Corporation Telerik Report Server: before 12.2.26.1007 — fixed in 12.2.26.1007

How to fix

Upgrade to a fixed version: Progress Software Corporation Telerik Report Server 12.2.26.1007. Check the vendor advisory for mitigations.

References

https://www.telerik.com/report-server/documentation/knowledge-base/kb-security-improper-neutralization-of-input-cve-2026-106155

Get alerted when CVE-2026-106155 or the next vulnerability affects your stack