CVE-2026-57858
HighCVSS 8.9Exploitation Probability (EPSS)
Low risk34th percentile - higher than 34% of all known CVEs
Summary
Cal.com Cal.diy versions 2.1.1 through 6.2.0 contain a stored cross-site scripting vulnerability in the BookingPageTagManager component that allows authenticated event owners to inject arbitrary JavaScript by supplying a malicious analytics tracking ID without sanitization. Attackers can close the inline script string literal with a crafted payload that executes in the browser of every visitor to the affected public booking page, enabling session cookie theft, forged authenticated requests, and wormable propagation by chaining with CSRF-able endpoints to persist payloads on additional events.
Risk Assessment
The risk includes session cookie theft, unauthorized actions on behalf of users, and potential propagation of the vulnerability to other events, which could lead to data integrity compromise and loss of user trust.
Recommendation
It is recommended to immediately upgrade to a patched version (if available) or apply temporary measures such as input validation and sanitization in the BookingPageTagManager component and restricting event owner privileges.
Original NVD description (English source)
Cal.com Cal.diy versions 2.1.1 through 6.2.0 contain a stored cross-site scripting vulnerability in the BookingPageTagManager component that allows authenticated event owners to inject arbitrary JavaScript by supplying a malicious analytics tracking ID without sanitization. Attackers can close the inline script string literal with a crafted payload that executes in the browser of every visitor to the affected public booking page, enabling session cookie theft, forged authenticated requests, and wormable propagation by chaining with CSRF-able endpoints to persist payloads on additional events.