What’s Vulnerable › Vulnerabilities
CVE-2025-66489: Cal.com Authentication Bypass via bad TOTP + password checks
- Severity: critical (CVSS 9.8 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.0% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2025-12-03 · updated 2026-10-18
- Weakness: CWE-303
Description
Cal.com is open-source scheduling software. Prior to 5.9.8, A flaw in the login credentials provider allows an attacker to bypass password verification when a TOTP code is provided, potentially gaining unauthorized access to user accounts. This issue exists due to problematic conditional logic in the authentication flow. This vulnerability is fixed in 5.9.8.
Affected products
- calcom cal.com: before 5.9.8 — fixed in 5.9.8
How to fix
Upgrade to a fixed version: calcom cal.com 5.9.8. Check the vendor advisory for mitigations.
References
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