CVE-2026-57858

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.

CVSS v3 8.9 HIGH

8.9^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
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/

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 13:17

Updated : 2026-08-13 16:18

NVD link : CVE-2026-57858

Mitre link : CVE-2026-57858

CVE.ORG link : CVE-2026-57858

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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