CVE-2026-57858

HIGH 8.9

Cal.com Cal.diy 6.2.0 Stored XSS via BookingPageTagManager Analytics Tracking ID

CVSS Score

8.9

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-79
Vendor	cal.com
Product	cal.com self-hosted (cal.diy)
Published	Aug 12, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Changed

Confidentiality

High

Integrity

High

Availability

Low

Affected Versions

Cal.com / Cal.com Self-Hosted (Cal.diy)

2.1.1 ≤ 6.2.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

Ashton Richards