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.
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/) 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.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 93.00 |
| Exploitation signal(No additional exploitation signal) | ×1.00 |
| VPI | 93.00 |
VPI formula vpi-v1
| Source | CVSS Version | Base Score | Severity | Vector String | Assessment Date |
|---|---|---|---|---|---|
| NVDNIST | 4.0 | 9.3 | CRITICAL | 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 | 07/24/2026 |
| NVDNIST | 3.1 |
| 8.9 |
HIGH |
| CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L |
| 07/24/2026 |