What’s Vulnerable › Vulnerabilities

CVE-2026-57858: Cal.com Cal.diy 6.2.0 Stored XSS via BookingPageTagManager Analytics Tracking ID

• Severity: high (CVSS 8.9 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-12 · updated 2026-10-24
• Weakness: CWE-79

Description

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.

Affected products

• Cal.com Self-Hosted (Cal.diy): from 2.1.1 through 6.2.0

References

• https://ashtonr.com/blog/cve-2026-57858/
• https://github.com/calcom/cal.com
• https://www.vulncheck.com/advisories/cal-com-cal-diy-stored-xss-via-bookingpagetagmanager-analytics-tracking-id
• https://ashtonr.com/blog/cve-2026-57858/

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