CVE-2025-66489

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.

CVSS 4.0

9.9CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:N

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

1.0% chance of exploitation in the next 30 days; higher than 61% of CVEs (scores of 2026-10-25)

CWE

CWE-303

Published

2025-12-03

Modified

2026-10-18

Record from

the NVD, synced 2026-10-19

Affected

• cal:cal.com

References

• https://github.com/calcom/cal.com/security/advisories/GHSA-9r3w-4j8q-pw98

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