CVE-2025-66489

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.

CVSS v3.1 Score

9.8

CRITICAL

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

Weakness Type (CWE)

CWE-303 CWE-303

Affected Products

Vendor	Product	Versions
cal	cal.com	< 5.9.8

References

Exploits

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

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2025-66489? +

CVE-2025-66489 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-66489? +

CVE-2025-66489 affects products from cal, specifically: cal.com. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-66489? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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