CVE-2025-66489NVD

Vulnerability Summary

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.

Severity Level

CRITICAL(9.9)

Published Date

Dec 3, 2025

Last Modified

Dec 3, 2025

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-303: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v4.0 Base Metrics — Score 9.9 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Attack RequirementsNone

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)High

Integrity (Vulnerable System)High

Availability (Vulnerable System)High

Confidentiality (Subsequent System)High

Integrity (Subsequent System)High

Availability (Subsequent System)None

Affected & Patched Versions

Affected Versions

Not provided by NVD for this CVE.

Patched Versions

Not provided by NVD for this CVE.

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