Advisories

Cal.com through 4.7.15 Cross-Site Scripting via booking questions

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severity
high
date
Affecting
  • cal.diy <= 4.7.15

CWE
  • CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
CVSS
9.3
CVSS V4 Vector
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
Credit
xyzeva
Description
Cal.com (repository calcom/cal.diy) in versions <= 4.7.15 is vulnerable to cross-site scripting (XSS) on the publicly accessible single booking view (e.g., /booking/<id>). Booking question (form field) labels are rendered via React's dangerouslySetInnerHTML without proper input sanitization or CSP, so an attacker who can create an event type with a malicious booking question label can inject arbitrary HTML/JavaScript that executes when a victim visits the booking view URL. Self-hosted instances with open registration are particularly at risk. The issue is fixed in version 4.7.16.

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