CVE-2026-9303: Calcom Cal.diy

Medium severity, CVSS 4.3. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability was identified in calcom cal.diy up to 4.9.4. Impacted is an unknown function. The manipulation leads to cross-site request forgery. It is possible to initiate the attack remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products

• Calcom Cal.diy: version 4.9.0 only; version 4.9.1 only; version 4.9.2 only; version 4.9.3 only; version 4.9.4 only

Published 2026-05-23. Last modified 2026-07-23.