Description
Cal.com (calcom/cal.diy) versions through 4.7.15 contain a stored cross-site scripting vulnerability. The single booking view (e.g., https://app.cal.com/booking/<id>) renders booking-question field labels via React's dangerouslySetInnerHTML without sanitizing or escaping user input. An attacker who can create an event type with a malicious booking-question label can inject arbitrary HTML/JavaScript that executes when a victim opens the crafted booking URL. The issue is fixed in v4.7.16.
References4
Metrics
- CVSS 3.1
-
8.9
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L - CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 36 · as of 14 November 2026
- CWE
- CWE-80
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