Home/CVE/Cal.com is open-source scheduling software. Prior to 5.9.8, A flaw in the login credentials provider allows an attacker
CVE

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

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.

CRITICAL · CVSS 9.8 EPSS 0.00275
Act now
  • Public exploit or PoC is available
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-303Incorrect Implementation of Authentication Algorithm
▤

Affected Products & Versions

1
cal cal.com< 5.9.8
⚠

Public Exploits & PoCs

1
pocgithub.com · GHSA-9r3w-4j8q-pw98github.com
▣

Scoring & Timeline

9.8
CRITICAL · CVSS v3.1 · security-advisories@github.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD03 Dec 2025 · 08:16 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
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