CVE-2026-16624

critical

Description

Cal.com OSS ships lacks authorization on webhook teamId creation, allowing any authenticated user to create a webhook on any team via unvalidated teamId injection, then steal booking data, including fields like organizer/attendee emails and custom responses, and conditionally video-call passwords, by triggering webhook delivery.

References

https://vokecyber.com/research/calcom-cross-tenant-webhook-plant

https://github.com/calcom/cal.diy/security/advisories/GHSA-4fwh-xxpv-xfm6

Details

Source: Mitre, NVD

Published: 2026-07-22

Updated: 2026-07-27

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:N

Severity: High

CVSS v3

Base Score: 9.6

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

Severity: Critical

EPSS

EPSS: 0.00219